diff --git a/non production apps/EscapeRoomApp/Docs/CHANGELOG.md b/non production apps/EscapeRoomApp/Docs/CHANGELOG.md
new file mode 100644
index 00000000..a6ff3e6a
--- /dev/null
+++ b/non production apps/EscapeRoomApp/Docs/CHANGELOG.md	
@@ -0,0 +1,39 @@
+# Changelog
+
+All notable changes to the BCTalent.EscapeRoom framework are documented here.
+
+---
+
+## [1.4.1.0] - 2026-09-14
+
+### Fixed
+
+- **Two rooms could be opened / venue closed prematurely** — `UpdateStatus()` on an already *Completed* room re-ran `OpenNextRoom()` unconditionally. Because that procedure looked for the next *Locked* room, it skipped the room that was already in progress and opened the one after it; once no locked room was left it stopped the venue even though rooms were still in progress. Pressing "Update Status", "Get Hint" or "Solve" on a completed room card (reachable from the room list and from the task-completed notification) triggered it.
+  - `OpenNextRoom()` is now idempotent: it exits when a later room is already InProgress, and closes the venue only via `CloseVenueIfCompleted()` (all rooms Completed).
+  - Room, task and venue status transitions re-read the row under an update lock and re-check the status before modifying, closing the race where the same completion ran in several sessions at once (e.g. event subscribers fired from the concurrency simulations' background sessions).
+  - Room/venue state is committed before the completion image is shown, so an interrupted session can no longer leave the next room locked.
+- Renamed a local variable named `Key` in codeunit 73925 "Escape Room Telemetry" (reserved word in current AL compilers, blocked the build).
+
+### Changed
+
+- `"Escape Room Venue".Stop()` and `CloseVenueIfCompleted()` now return `Boolean` (true when the venue got completed by that call) and no longer show the completion image themselves; `"Escape Room".Stop()` shows it.
+
+---
+
+## [1.4.0.0] - 2026-06-10
+
+### Added
+
+- **Custom Telemetry Events API** — New public `LogCustomEvent` overloads on codeunit 73925 "Escape Room Telemetry" allow room extension apps to emit custom scoring and diagnostic events.
+  - Task-scoped and room-scoped variants
+  - Optional `ExtraDimensions` parameter for caller-provided custom dimensions
+  - Score clamped to -5..+5 to keep leaderboards balanced
+  - All custom events use the fixed event name `EscapeRoomCustomEvent` with `EventSource = Custom` dimension
+- **Custom Events Overview** KQL query in `LeaderboardQueries.kql` for facilitator auditing
+- All scoring KQL queries and dashboard tiles now include `EscapeRoomCustomEvent`
+
+---
+
+## [1.3.x] - Previous releases
+
+Initial framework with seven built-in telemetry events, interface-based venue/room/task system, leaderboard KQL queries, and Azure Data Explorer dashboard.
diff --git a/non production apps/EscapeRoomApp/Docs/Dev/API-Reference.md b/non production apps/EscapeRoomApp/Docs/Dev/API-Reference.md
index fca4b266..7f7e94a0 100644
--- a/non production apps/EscapeRoomApp/Docs/Dev/API-Reference.md	
+++ b/non production apps/EscapeRoomApp/Docs/Dev/API-Reference.md	
@@ -527,6 +527,52 @@ procedure UpdateStatus()
 
 ---
 
+## Telemetry API — Codeunit 73925 "Escape Room Telemetry"
+
+### Built-in Event Procedures
+
+```al
+procedure LogFinishedTask(var Task: Record "Escape Room Task")
+procedure LogHintRequested(var Task: Record "Escape Room Task")
+procedure LogSolutionRequested(var Room: record "Escape Room")
+procedure LogRoomStarted(var Room: Record "Escape Room")
+procedure LogRoomCompleted(var Room: Record "Escape Room")
+procedure LogVenueCompleted(var Venue: Record "Escape Room Venue")
+procedure LogNotification(NotificationText: Text)
+```
+
+### Custom Event Procedures
+
+```al
+/// Task-scoped custom event (standard task/room/venue dimensions added automatically)
+procedure LogCustomEvent(var EscapeRoomTask: Record "Escape Room Task"; EventId: Text; EventMessage: Text; ScorePoints: Integer)
+
+/// Room-scoped custom event (standard room/venue dimensions added automatically)
+procedure LogCustomEvent(var EscapeRoom: Record "Escape Room"; EventId: Text; EventMessage: Text; ScorePoints: Integer)
+
+/// Task-scoped custom event with additional caller-provided dimensions
+procedure LogCustomEvent(var EscapeRoomTask: Record "Escape Room Task"; EventId: Text; EventMessage: Text; ScorePoints: Integer; ExtraDimensions: Dictionary of [Text, Text])
+
+/// Room-scoped custom event with additional caller-provided dimensions
+procedure LogCustomEvent(var EscapeRoom: Record "Escape Room"; EventId: Text; EventMessage: Text; ScorePoints: Integer; ExtraDimensions: Dictionary of [Text, Text])
+```
+
+**Parameters:**
+- `EventId` — Caller-defined identifier (max 80 chars, trimmed; empty defaults to `Unspecified`). Recommend prefix with venue id, e.g. `DEV1-EasterEggFound`.
+- `EventMessage` — Human-readable message logged to Application Insights.
+- `ScorePoints` — Points added to leaderboard, clamped to -5..+5.
+- `ExtraDimensions` — Optional additional dimensions. Keys that conflict with standard dimensions are silently skipped.
+
+**Behavior:**
+- Application Insights event name is always `EscapeRoomCustomEvent`.
+- Adds `EventId` and `EventSource = Custom` dimensions automatically.
+- Standard dimensions (VenueId, VenueName, RoomName, TaskName, ScorePoints, etc.) cannot be overwritten by caller.
+- Never throws — defensive against empty records.
+
+See [Telemetry Integration](../Framework/Telemetry-Integration.md#custom-events-for-room-developers) for full documentation.
+
+---
+
 ## Backward Compatibility Guarantee
 
 **Framework Version 1.x Promise:**
@@ -553,4 +599,4 @@ procedure UpdateStatus()
 
 ---
 
-**Last Updated:** January 7, 2026
+**Last Updated:** June 10, 2026
diff --git a/non production apps/EscapeRoomApp/Docs/Framework/Architecture.md b/non production apps/EscapeRoomApp/Docs/Framework/Architecture.md
index 3ba60807..d7b0dc13 100644
--- a/non production apps/EscapeRoomApp/Docs/Framework/Architecture.md	
+++ b/non production apps/EscapeRoomApp/Docs/Framework/Architecture.md	
@@ -363,9 +363,11 @@ codeunit 50103 "My Task Validation" implements "IEscape Room Task Validation"
 9. Telemetry tracks all events for leaderboard
 
 **Room Navigation:**
-- `OpenNextRoom()` procedure finds next room by sequence
-- Sets current key and ascending order for proper ordering
-- Only InProgress or NotStarted rooms can be opened
+- `OpenNextRoom()` opens the first *Locked* room with a higher sequence than the room that was just completed
+- It is idempotent: when a later room is already *InProgress* it does nothing, so calling it twice (concurrent sessions, or "Update Status" pressed on an already completed room) can never open a second room
+- When no later room is left, it calls `CloseVenueIfCompleted()`, which closes the venue only when *every* room is Completed
+- All status transitions (`Start()`, `Stop()` on rooms and tasks, `Stop()` on the venue) re-read the row under an update lock (`ReadIsolation = UpdLock`) and re-check the status before modifying, so two sessions completing the same task/room serialize instead of both performing the transition
+- State transitions are committed *before* the completion image is shown, so an interrupted or UI-less (background) session cannot leave the next room locked
 
 ---
 
@@ -398,12 +400,19 @@ procedure Start()
 
 ```al
 procedure UpdateStatus()
-// Checks task completion and updates room status
+// Re-validates open tasks and completes the room when none remain
+// On an already completed room it only runs the (idempotent) OpenNextRoom() recovery
 
 procedure CloseRoomIfCompleted()
-// Sets room to Completed when all tasks done
-// Opens next room automatically
-// Logs telemetry for room completion
+// Completes the room when all tasks are done (calls Stop())
+
+procedure Stop()
+// Locks the row, sets Completed, commits, logs telemetry,
+// opens the next room (or closes the venue), then shows the completion image(s)
+
+internal procedure OpenNextRoom() VenueCompleted: Boolean
+// Opens the next Locked room; no-op when a later room is InProgress
+// Returns true when the venue got completed by this call
 ```
 
 ### Escape Room Task Table Procedures
diff --git a/non production apps/EscapeRoomApp/Docs/Framework/Creating-Rooms.md b/non production apps/EscapeRoomApp/Docs/Framework/Creating-Rooms.md
index ce47a43b..db9bb135 100644
--- a/non production apps/EscapeRoomApp/Docs/Framework/Creating-Rooms.md	
+++ b/non production apps/EscapeRoomApp/Docs/Framework/Creating-Rooms.md	
@@ -1011,6 +1011,22 @@ Once your venue is created:
 
 ---
 
+## Custom Scoring with Telemetry
+
+Room apps can emit custom telemetry events for bonus challenges, easter eggs, or penalties using the `LogCustomEvent` overloads on codeunit 73925 "Escape Room Telemetry". Custom events carry the same standard dimensions as built-in events and participate in the leaderboard scoring pipeline (score clamped to -5..+5).
+
+```al
+var
+    EscapeRoomTelemetry: Codeunit "Escape Room Telemetry";
+begin
+    EscapeRoomTelemetry.LogCustomEvent(Task, 'DEV1-BonusChallenge', 'Participant completed the bonus challenge.', 2);
+end;
+```
+
+See [Telemetry Integration - Custom Events](Telemetry-Integration.md#custom-events-for-room-developers) for the full API reference, clamping rules, and EventId conventions.
+
+---
+
 ## Related Documentation
 
 - [Architecture Overview](Architecture.md) - Framework design patterns
@@ -1020,4 +1036,4 @@ Once your venue is created:
 
 ---
 
-**Last Updated:** January 7, 2026
+**Last Updated:** June 10, 2026
diff --git a/non production apps/EscapeRoomApp/Docs/Framework/Telemetry-Integration.md b/non production apps/EscapeRoomApp/Docs/Framework/Telemetry-Integration.md
index e9ef9434..f27142d5 100644
--- a/non production apps/EscapeRoomApp/Docs/Framework/Telemetry-Integration.md	
+++ b/non production apps/EscapeRoomApp/Docs/Framework/Telemetry-Integration.md	
@@ -110,6 +110,24 @@ The framework logs seven distinct event types:
 
 ---
 
+#### 8. **EscapeRoomCustomEvent**
+
+**When:** Room extension app calls `LogCustomEvent(...)` to emit a custom scoring or diagnostic event  
+**Score Impact:** -5 to +5 points (caller-defined, clamped)  
+**Custom Dimensions:**
+- VenueId, VenueName
+- PartnerName, FullName
+- RoomName
+- TaskName (when task-scoped)
+- ScorePoints (clamped to -5..+5)
+- EventId (caller-provided identifier, max 80 chars)
+- EventSource: `Custom`
+- Any additional caller-provided dimensions (cannot overwrite standard keys)
+
+**Logged By:** `LogCustomEvent(...)` overloads
+
+---
+
 ## Scoring System
 
 ### Point Values
@@ -122,6 +140,7 @@ The framework logs seven distinct event types:
 | Request hint | **-1** | EscapeRoomHintRequested |
 | View solution | **-3** | EscapeRoomSolutionRequested |
 | Start room | **0** | EscapeRoomStarted |
+| Custom event | **-5..+5** (caller-defined) | EscapeRoomCustomEvent |
 
 ### Scoring Examples
 
@@ -159,6 +178,10 @@ procedure LogRoomStarted(var Room: Record "Escape Room")
 procedure LogRoomCompleted(var Room: Record "Escape Room")
 procedure LogVenueCompleted(var Venue: Record "Escape Room Venue")
 procedure LogNotification(NotificationText: Text)
+procedure LogCustomEvent(var EscapeRoomTask: Record "Escape Room Task"; EventId: Text; EventMessage: Text; ScorePoints: Integer)
+procedure LogCustomEvent(var EscapeRoom: Record "Escape Room"; EventId: Text; EventMessage: Text; ScorePoints: Integer)
+procedure LogCustomEvent(var EscapeRoomTask: Record "Escape Room Task"; EventId: Text; EventMessage: Text; ScorePoints: Integer; ExtraDimensions: Dictionary of [Text, Text])
+procedure LogCustomEvent(var EscapeRoom: Record "Escape Room"; EventId: Text; EventMessage: Text; ScorePoints: Integer; ExtraDimensions: Dictionary of [Text, Text])
 ```
 
 **Internal Procedures:**
@@ -221,6 +244,54 @@ Every telemetry event includes rich context:
 
 ---
 
+## Custom Events (for room developers)
+
+Room extension apps can emit custom telemetry events using the `LogCustomEvent` overloads on codeunit 73925. Custom events participate in the standard leaderboard scoring pipeline.
+
+### API Signatures
+
+```al
+// Task-scoped (includes task + room + venue dimensions)
+procedure LogCustomEvent(var EscapeRoomTask: Record "Escape Room Task"; EventId: Text; EventMessage: Text; ScorePoints: Integer)
+procedure LogCustomEvent(var EscapeRoomTask: Record "Escape Room Task"; EventId: Text; EventMessage: Text; ScorePoints: Integer; ExtraDimensions: Dictionary of [Text, Text])
+
+// Room-scoped (includes room + venue dimensions)
+procedure LogCustomEvent(var EscapeRoom: Record "Escape Room"; EventId: Text; EventMessage: Text; ScorePoints: Integer)
+procedure LogCustomEvent(var EscapeRoom: Record "Escape Room"; EventId: Text; EventMessage: Text; ScorePoints: Integer; ExtraDimensions: Dictionary of [Text, Text])
+```
+
+### Usage Example
+
+```al
+// Award a bonus point when participant discovers an easter egg
+procedure OnEasterEggFound(var Task: Record "Escape Room Task")
+var
+    EscapeRoomTelemetry: Codeunit "Escape Room Telemetry";
+begin
+    EscapeRoomTelemetry.LogCustomEvent(
+        Task,
+        'DEV1-EasterEggFound',
+        'Participant discovered the hidden easter egg in Room 3.',
+        2  // +2 bonus points
+    );
+end;
+```
+
+### Rules
+
+- **Score clamping:** `ScorePoints` is clamped to **-5..+5**. Values outside this range are silently clamped to the nearest bound.
+- **EventId convention:** Prefix with your venue/app id, e.g. `DEV1-EasterEggFound`. Max 80 characters; empty defaults to `Unspecified`.
+- **Event name:** All custom events use the fixed Application Insights message `EscapeRoomCustomEvent`. The caller's `EventId` is a custom dimension — not the event name.
+- **EventSource dimension:** Always set to `Custom` to distinguish from built-in framework events.
+- **No overwriting standard dimensions:** Caller-provided `ExtraDimensions` cannot overwrite standard keys (`VenueId`, `VenueName`, `RoomName`, `TaskName`, `ScorePoints`, `EventId`, `EventSource`, etc.). Conflicting keys are silently skipped.
+- **Never throws:** The telemetry call is defensive — empty records produce empty dimension values, same as built-in behavior.
+
+### Leaderboard Impact
+
+Custom events flow into the standard leaderboard queries. The `ScorePoints` dimension is summed alongside all other scoring events. Use the "Custom Events Overview" query in `LeaderboardQueries.kql` to audit custom scoring during events.
+
+---
+
 ## Leaderboard Queries
 
 ### KQL Queries
@@ -446,4 +517,4 @@ end;
 
 ---
 
-**Last Updated:** January 7, 2026
+**Last Updated:** June 10, 2026
diff --git a/non production apps/EscapeRoomApp/Leaderboard/LeaderboardQueries.kql b/non production apps/EscapeRoomApp/Leaderboard/LeaderboardQueries.kql
index e41852e5..e4179222 100644
--- a/non production apps/EscapeRoomApp/Leaderboard/LeaderboardQueries.kql	
+++ b/non production apps/EscapeRoomApp/Leaderboard/LeaderboardQueries.kql	
@@ -51,6 +51,7 @@ EscapeRoomData
     VenuesCompleted = countif(eventId == "ALEscapeRoomVenueCompleted"),
     HintsUsed = countif(eventId == "ALEscapeRoomHintRequested"),
     SolutionsUsed = countif(eventId == "ALEscapeRoomSolutionRequested"),
+    CustomEvents = countif(eventId == "ALEscapeRoomCustomEvent"),
     LastActivity = max(taskStopDateTime),
     FastestVenueCompletion = min(VenueCompletionTimeMinutes)
     by Attendee, userId, Partner, environmentName
@@ -83,12 +84,14 @@ EscapeRoomData
     VenueBonusPoints = sumif(Score, eventId == "ALEscapeRoomVenueCompleted"),
     HintPenalty = sumif(Score, eventId == "ALEscapeRoomHintRequested"),
     SolutionPenalty = sumif(Score, eventId == "ALEscapeRoomSolutionRequested"),
+    CustomEventPoints = sumif(Score, eventId == "ALEscapeRoomCustomEvent"),
     TotalScore = sum(Score),
     TasksCompleted = countif(eventId == "ALEscapeRoomTaskFinished"),
     RoomsCompleted = countif(eventId == "ALEscapeRoomCompleted"),
     VenuesCompleted = countif(eventId == "ALEscapeRoomVenueCompleted"),
     HintsUsed = countif(eventId == "ALEscapeRoomHintRequested"),
     SolutionsUsed = countif(eventId == "ALEscapeRoomSolutionRequested"),
+    CustomEvents = countif(eventId == "ALEscapeRoomCustomEvent"),
     FastestVenueCompletion = min(VenueCompletionTimeMinutes)
     by Attendee, Partner, environmentName
 | extend 
@@ -107,11 +110,13 @@ EscapeRoomData
     VenueBonusPoints,
     HintPenalty,
     SolutionPenalty,
+    CustomEventPoints,
     ScoreEfficiency,
     CompletionTimeMinutes,
     TasksCompleted,
     HintsUsed,
-    SolutionsUsed
+    SolutionsUsed,
+    CustomEvents
 | order by TotalScore desc, CompletionTimeMinutes asc nulls last
 
 // =================================================================
@@ -139,4 +144,22 @@ EscapeRoomData
     CompletionTimeMinutes,
     FinalScore,
     CompletionDate
-| order by CompletionTimeMinutes asc
\ No newline at end of file
+| order by CompletionTimeMinutes asc
+
+// =================================================================
+// Query 4: Custom Events Overview
+// =================================================================
+EscapeRoomData
+| where eventId == "ALEscapeRoomCustomEvent"
+| extend
+    CustomEventId = tostring(customDimensions.alEventId),
+    EventSource = tostring(customDimensions.alEventSource)
+| project
+    timestamp,
+    Attendee,
+    Partner,
+    venueId,
+    roomName,
+    CustomEventId,
+    Score
+| order by timestamp desc
\ No newline at end of file
diff --git a/non production apps/EscapeRoomApp/Leaderboard/LeaderboardSetup.md b/non production apps/EscapeRoomApp/Leaderboard/LeaderboardSetup.md
index 0c061052..211da722 100644
--- a/non production apps/EscapeRoomApp/Leaderboard/LeaderboardSetup.md	
+++ b/non production apps/EscapeRoomApp/Leaderboard/LeaderboardSetup.md	
@@ -173,6 +173,11 @@ The queries work with these primary event types:
 - **`ALEscapeRoomHintRequested`**: Hint usage with penalty
 - **`ALEscapeRoomSolutionRequested`**: Solution usage with penalty
 - **`ALEscapeRoomStarted`**: Room/venue start tracking
+- **`ALEscapeRoomCustomEvent`**: Custom events emitted by room extensions (score -5..+5)
+
+### Custom Events & Scoring
+
+Room extension apps can emit custom telemetry events that participate in leaderboard scoring. These events use the `EscapeRoomCustomEvent` event name and carry a caller-defined score (clamped to -5..+5). Use the **"Custom Events Overview"** query in `LeaderboardQueries.kql` to audit custom scoring during an event — it lists timestamp, attendee, partner, venue, room, EventId, and ScorePoints for all custom events.
 
 ### Calculated Fields  
 - **`durationMinutes`**: Calculated from start/stop timestamps
diff --git a/non production apps/EscapeRoomApp/Leaderboard/dashboard-BCTalent.EscapeRooms.json b/non production apps/EscapeRoomApp/Leaderboard/dashboard-BCTalent.EscapeRooms.json
index b5c8abe4..d40cdcaa 100644
--- a/non production apps/EscapeRoomApp/Leaderboard/dashboard-BCTalent.EscapeRooms.json	
+++ b/non production apps/EscapeRoomApp/Leaderboard/dashboard-BCTalent.EscapeRooms.json	
@@ -684,7 +684,7 @@
                 "kind": "inline",
                 "dataSourceId": "803c0786-1793-49b9-8c52-5d977ac0c74c"
             },
-            "text": "EscapeRoomData\n| where isnotempty(Attendee) and isnotempty(Score) and isnotempty( Partner)\n| extend AttendeePartner = strcat(Attendee,\" (\",Partner,\")\")\n| summarize \n    TotalScore = sum(Score),\n    TasksCompleted = countif(eventId == \"ALEscapeRoomTaskFinished\"),\n    RoomsCompleted = countif(eventId == \"ALEscapeRoomCompleted\"),\n    VenuesCompleted = countif(eventId == \"ALEscapeRoomVenueCompleted\"),\n    HintsUsed = countif(eventId == \"ALEscapeRoomHintRequested\"),\n    SolutionsUsed = countif(eventId == \"ALEscapeRoomSolutionRequested\"),\n    LastActivity = max(taskStopDateTime)\n    by AttendeePartner, userId, Partner, environmentName\n| order by TotalScore desc\n| extend Rank = row_number()\n| where Rank <= 10\n| project \n    Rank,\n    AttendeePartner,\n    Partner,\n    TotalScore,\n    TasksCompleted,\n    RoomsCompleted,\n    VenuesCompleted,\n    HintsUsed,\n    SolutionsUsed,\n    LastActivity\n| order by TotalScore desc",
+            "text": "EscapeRoomData\n| where isnotempty(Attendee) and isnotempty(Score) and isnotempty( Partner)\n| extend AttendeePartner = strcat(Attendee,\" (\",Partner,\")\")\n| summarize \n    TotalScore = sum(Score),\n    TasksCompleted = countif(eventId == \"ALEscapeRoomTaskFinished\"),\n    RoomsCompleted = countif(eventId == \"ALEscapeRoomCompleted\"),\n    VenuesCompleted = countif(eventId == \"ALEscapeRoomVenueCompleted\"),\n    HintsUsed = countif(eventId == \"ALEscapeRoomHintRequested\"),\n    SolutionsUsed = countif(eventId == \"ALEscapeRoomSolutionRequested\"),\n    CustomEvents = countif(eventId == \"ALEscapeRoomCustomEvent\"),\n    LastActivity = max(taskStopDateTime)\n    by AttendeePartner, userId, Partner, environmentName\n| order by TotalScore desc\n| extend Rank = row_number()\n| where Rank <= 10\n| project \n    Rank,\n    AttendeePartner,\n    Partner,\n    TotalScore,\n    TasksCompleted,\n    RoomsCompleted,\n    VenuesCompleted,\n    HintsUsed,\n    SolutionsUsed,\n    CustomEvents,\n    LastActivity\n| order by TotalScore desc",
             "id": "8a6d557a-34b9-4cad-8f4b-82a33fb0b883",
             "usedVariables": [
                 "EscapeRoomData"
@@ -706,7 +706,7 @@
                 "kind": "inline",
                 "dataSourceId": "803c0786-1793-49b9-8c52-5d977ac0c74c"
             },
-            "text": "EscapeRoomData\n| where isnotempty(Attendee) and isnotempty(Score) and isnotempty(Partner)\n| summarize \n    TaskPoints = sumif(Score, eventId == \"ALEscapeRoomTaskFinished\"),\n    RoomBonusPoints = sumif(Score, eventId == \"ALEscapeRoomCompleted\"),\n    VenueBonusPoints = sumif(Score, eventId == \"ALEscapeRoomVenueCompleted\"),\n    HintPenalty = sumif(Score, eventId == \"ALEscapeRoomHintRequested\"),\n    SolutionPenalty = sumif(Score, eventId == \"ALEscapeRoomSolutionRequested\"),\n    TotalScore = sum(Score),\n    TasksCompleted = countif(eventId == \"ALEscapeRoomTaskFinished\"),\n    RoomsCompleted = countif(eventId == \"ALEscapeRoomCompleted\"),\n    VenuesCompleted = countif(eventId == \"ALEscapeRoomVenueCompleted\"),\n    HintsUsed = countif(eventId == \"ALEscapeRoomHintRequested\"),\n    SolutionsUsed = countif(eventId == \"ALEscapeRoomSolutionRequested\"),\n    FastestVenueCompletion = min(VenueCompletionTimeMinutes)\n    by Attendee, Partner, environmentName\n| extend \n    ScoreEfficiency = iif((TasksCompleted + HintsUsed + SolutionsUsed) > 0, round((todouble(TotalScore) / (TasksCompleted + HintsUsed + SolutionsUsed)) * 100) / 100, todouble(0)),\n    CompletionTimeMinutes = iff(isnull(FastestVenueCompletion), real(null), round(FastestVenueCompletion, 2))\n| order by TotalScore desc, CompletionTimeMinutes asc nulls last\n| extend Rank = row_number()\n| where Rank <= 10\n| project \n    Rank,\n    Attendee,\n    Partner,\n    TotalScore,\n    TaskPoints,\n    RoomBonusPoints,\n    VenueBonusPoints,\n    HintPenalty,\n    SolutionPenalty,\n    ScoreEfficiency,\n    CompletionTimeMinutes,\n    TasksCompleted,\n    HintsUsed,\n    SolutionsUsed\n| order by TotalScore desc, CompletionTimeMinutes asc  nulls last\n",
+            "text": "EscapeRoomData\n| where isnotempty(Attendee) and isnotempty(Score) and isnotempty(Partner)\n| summarize \n    TaskPoints = sumif(Score, eventId == \"ALEscapeRoomTaskFinished\"),\n    RoomBonusPoints = sumif(Score, eventId == \"ALEscapeRoomCompleted\"),\n    VenueBonusPoints = sumif(Score, eventId == \"ALEscapeRoomVenueCompleted\"),\n    HintPenalty = sumif(Score, eventId == \"ALEscapeRoomHintRequested\"),\n    SolutionPenalty = sumif(Score, eventId == \"ALEscapeRoomSolutionRequested\"),\n    CustomEventPoints = sumif(Score, eventId == \"ALEscapeRoomCustomEvent\"),\n    TotalScore = sum(Score),\n    TasksCompleted = countif(eventId == \"ALEscapeRoomTaskFinished\"),\n    RoomsCompleted = countif(eventId == \"ALEscapeRoomCompleted\"),\n    VenuesCompleted = countif(eventId == \"ALEscapeRoomVenueCompleted\"),\n    HintsUsed = countif(eventId == \"ALEscapeRoomHintRequested\"),\n    SolutionsUsed = countif(eventId == \"ALEscapeRoomSolutionRequested\"),\n    CustomEvents = countif(eventId == \"ALEscapeRoomCustomEvent\"),\n    FastestVenueCompletion = min(VenueCompletionTimeMinutes)\n    by Attendee, Partner, environmentName\n| extend \n    ScoreEfficiency = iif((TasksCompleted + HintsUsed + SolutionsUsed) > 0, round((todouble(TotalScore) / (TasksCompleted + HintsUsed + SolutionsUsed)) * 100) / 100, todouble(0)),\n    CompletionTimeMinutes = iff(isnull(FastestVenueCompletion), real(null), round(FastestVenueCompletion, 2))\n| order by TotalScore desc, CompletionTimeMinutes asc nulls last\n| extend Rank = row_number()\n| where Rank <= 10\n| project \n    Rank,\n    Attendee,\n    Partner,\n    TotalScore,\n    TaskPoints,\n    RoomBonusPoints,\n    VenueBonusPoints,\n    HintPenalty,\n    SolutionPenalty,\n    CustomEventPoints,\n    ScoreEfficiency,\n    CompletionTimeMinutes,\n    TasksCompleted,\n    HintsUsed,\n    SolutionsUsed,\n    CustomEvents\n| order by TotalScore desc, CompletionTimeMinutes asc  nulls last\n",
             "id": "e56b8546-96f6-4a9a-b0d8-6fdf90363676",
             "usedVariables": [
                 "EscapeRoomData"
@@ -717,7 +717,7 @@
                 "kind": "inline",
                 "dataSourceId": "803c0786-1793-49b9-8c52-5d977ac0c74c"
             },
-            "text": "EscapeRoomData\n| where isnotempty(Attendee) and isnotempty(Score) and isnotempty(Partner)\n| summarize \n    TotalScore = sum(Score),\n    TasksCompleted = countif(eventId == \"ALEscapeRoomTaskFinished\"),\n    RoomsCompleted = countif(eventId == \"ALEscapeRoomCompleted\"),\n    VenuesCompleted = countif(eventId == \"ALEscapeRoomVenueCompleted\"),\n    HintsUsed = countif(eventId == \"ALEscapeRoomHintRequested\"),\n    SolutionsUsed = countif(eventId == \"ALEscapeRoomSolutionRequested\"),\n    LastActivity = max(taskStopDateTime),\n    FastestVenueCompletion = min(VenueCompletionTimeMinutes)\n    by Attendee, userId, Partner, environmentName\n| extend CompletionTimeMinutes = iff(isnull(FastestVenueCompletion), real(null), round(FastestVenueCompletion, 2))\n| order by TotalScore desc, CompletionTimeMinutes asc nulls last\n| extend Rank = row_number()\n| where Rank <= 100\n| project \n    Rank,\n    Attendee,\n    Partner,\n    TotalScore,\n    TasksCompleted,\n    RoomsCompleted,\n    VenuesCompleted,\n    HintsUsed,\n    SolutionsUsed,\n    CompletionTimeMinutes,\n    LastActivity\n| order by TotalScore desc, CompletionTimeMinutes asc nulls last",
+            "text": "EscapeRoomData\n| where isnotempty(Attendee) and isnotempty(Score) and isnotempty(Partner)\n| summarize \n    TotalScore = sum(Score),\n    TasksCompleted = countif(eventId == \"ALEscapeRoomTaskFinished\"),\n    RoomsCompleted = countif(eventId == \"ALEscapeRoomCompleted\"),\n    VenuesCompleted = countif(eventId == \"ALEscapeRoomVenueCompleted\"),\n    HintsUsed = countif(eventId == \"ALEscapeRoomHintRequested\"),\n    SolutionsUsed = countif(eventId == \"ALEscapeRoomSolutionRequested\"),\n    CustomEvents = countif(eventId == \"ALEscapeRoomCustomEvent\"),\n    LastActivity = max(taskStopDateTime),\n    FastestVenueCompletion = min(VenueCompletionTimeMinutes)\n    by Attendee, userId, Partner, environmentName\n| extend CompletionTimeMinutes = iff(isnull(FastestVenueCompletion), real(null), round(FastestVenueCompletion, 2))\n| order by TotalScore desc, CompletionTimeMinutes asc nulls last\n| extend Rank = row_number()\n| where Rank <= 100\n| project \n    Rank,\n    Attendee,\n    Partner,\n    TotalScore,\n    TasksCompleted,\n    RoomsCompleted,\n    VenuesCompleted,\n    HintsUsed,\n    SolutionsUsed,\n    CustomEvents,\n    CompletionTimeMinutes,\n    LastActivity\n| order by TotalScore desc, CompletionTimeMinutes asc nulls last",
             "id": "bc7c2e02-ff93-443d-93c0-a1e0db76e80c",
             "usedVariables": [
                 "EscapeRoomData"
diff --git a/non production apps/EscapeRoomApp/Src/1.Venue/EscapeRoomVenue.Table.al b/non production apps/EscapeRoomApp/Src/1.Venue/EscapeRoomVenue.Table.al
index 871dc2d7..e8335608 100644
--- a/non production apps/EscapeRoomApp/Src/1.Venue/EscapeRoomVenue.Table.al	
+++ b/non production apps/EscapeRoomApp/Src/1.Venue/EscapeRoomVenue.Table.al	
@@ -92,19 +92,34 @@ table 73926 "Escape Room Venue"
         Rec.StartFirstRoom();
     end;
 
-    procedure Stop()
+    /// <summary>
+    /// Marks the venue as completed. Idempotent: a venue that already has a Stop DateTime is left alone.
+    /// Showing the completion image is up to the caller (see "Escape Room".Stop()).
+    /// </summary>
+    /// <returns>True when the venue got completed by this call.</returns>
+    procedure Stop(): Boolean
     var
-        Venue: Interface iEscapeRoomVenue;
-        EscapeRoomNotifications: Codeunit EscapeRoomNotifications;
         EscapeRoomTelemetry: Codeunit "Escape Room Telemetry";
     begin
+        if not LockAndRefresh() then exit(false);
+        if Rec."Stop DateTime" <> 0DT then exit(false);
+
         Rec."Stop DateTime" := CurrentDateTime();
         Rec.Modify();
+        Commit();
 
-        Commit;
-
-        EscapeRoomNotifications.venueFinished(Rec);
         EscapeRoomTelemetry.LogVenueCompleted(Rec);
+        exit(true);
+    end;
+
+    local procedure LockAndRefresh(): Boolean
+    var
+        Found: Boolean;
+    begin
+        Rec.ReadIsolation := IsolationLevel::UpdLock;
+        Found := Rec.Find('=');
+        Rec.ReadIsolation := IsolationLevel::Default;
+        exit(Found);
     end;
 
     procedure StartFirstRoom()
@@ -119,15 +134,16 @@ table 73926 "Escape Room Venue"
         Room.Start();
     end;
 
-    procedure CloseVenueIfCompleted()
+    /// <returns>True when the venue got completed by this call.</returns>
+    procedure CloseVenueIfCompleted(): Boolean
     var
         Room: Record "Escape Room";
     begin
         Room.Setrange("Venue Id", Rec.Id);
         Room.SetFilter(Status, '<>%1', Room.Status::Completed);
-        if not Room.IsEmpty then exit;
+        if not Room.IsEmpty then exit(false);
 
-        Rec.Stop();
+        exit(Rec.Stop());
     end;
 
     procedure RefreshRooms()
diff --git a/non production apps/EscapeRoomApp/Src/2.Room/EscapeRoom.Table.al b/non production apps/EscapeRoomApp/Src/2.Room/EscapeRoom.Table.al
index befb5d9b..37b9b333 100644
--- a/non production apps/EscapeRoomApp/Src/2.Room/EscapeRoom.Table.al	
+++ b/non production apps/EscapeRoomApp/Src/2.Room/EscapeRoom.Table.al	
@@ -89,9 +89,18 @@ table 73920 "Escape Room"
     procedure UpdateStatus()
     var
         Task: Record "Escape Room Task";
+        Venue: Record "Escape Room Venue";
+        EscapeRoomNotifications: Codeunit EscapeRoomNotifications;
     begin
         if Rec.Status = Rec.Status::Completed then begin
-            OpenNextRoom();
+            // Recovery path only: if this room was completed but the next room never got started
+            // (e.g. the session was interrupted), open it now. OpenNextRoom() is idempotent and does
+            // nothing while a later room is already in progress, so pressing "Update Status" on a
+            // completed room can never open a second room or close the venue prematurely.
+            if OpenNextRoom() then begin
+                Venue.Get(Rec."Venue Id");
+                EscapeRoomNotifications.VenueFinished(Venue);
+            end;
             exit;
         end;
 
@@ -113,8 +122,6 @@ table 73920 "Escape Room"
         if not Task.IsEmpty() then exit;
 
         Rec.Stop();
-
-        OpenNextRoom();
     end;
 
     procedure CloseRoomIfCompleted()
@@ -129,59 +136,102 @@ table 73920 "Escape Room"
         if not task.IsEmpty then exit;
 
         Rec.Stop();
-
-        OpenNextRoom();
     end;
 
-    internal procedure OpenNextRoom()
+    /// <summary>
+    /// Opens the next locked room after this one, or closes the venue when every room is completed.
+    /// Idempotent: does nothing when a later room is already in progress.
+    /// </summary>
+    /// <returns>True when the venue got completed by this call.</returns>
+    internal procedure OpenNextRoom() VenueCompleted: Boolean
     var
         NextRoom: Record "Escape Room";
         Venue: Record "Escape Room Venue";
     begin
+        NextRoom.ReadIsolation := IsolationLevel::UpdLock;
         NextRoom.SetCurrentKey(Sequence);
         NextRoom.Ascending := true;
         NextRoom.SetRange("Venue Id", Rec."Venue Id");
         NextRoom.SetFilter(Sequence, '>%1', Rec.Sequence);
+
+        // A later room is already open: nothing to do. This is what prevents a second room from
+        // being opened when this procedure runs twice (concurrent sessions, or "Update Status"
+        // pressed on an already completed room).
+        NextRoom.SetRange(Status, NextRoom.Status::InProgress);
+        if NextRoom.FindFirst() then
+            exit(false);
+
         NextRoom.SetRange(Status, NextRoom.Status::Locked);
         if NextRoom.FindFirst() then begin
             NextRoom.Start();
-        end
-        else begin
-            Venue.Get(Rec."Venue Id");
-            Venue.Stop();
+            exit(false);
         end;
+
+        // No later room left to open. Close the venue, but only when every room is really completed.
+        Venue.Get(Rec."Venue Id");
+        exit(Venue.CloseVenueIfCompleted());
     end;
 
     procedure Start()
     var
         EscapeRoomTelemetry: Codeunit "Escape Room Telemetry";
     begin
-        if Rec.Status = Rec.Status::Locked then begin
-            Rec.Status := Rec.Status::InProgress;
-            Rec."Start DateTime" := CurrentDateTime();
-            Rec.Modify();
-            Commit();
+        if not LockAndRefresh() then exit;
+        if Rec.Status <> Rec.Status::Locked then exit;
 
-            EscapeRoomTelemetry.LogRoomStarted(Rec);
-        end;
+        Rec.Status := Rec.Status::InProgress;
+        Rec."Start DateTime" := CurrentDateTime();
+        Rec.Modify();
+        Commit();
+
+        EscapeRoomTelemetry.LogRoomStarted(Rec);
     end;
 
+    /// <summary>
+    /// Completes this room, opens the next one and then shows the completion image(s).
+    /// The state transitions are committed before any UI is shown, so an interrupted or
+    /// UI-less (background) session can no longer leave the next room locked.
+    /// </summary>
     procedure Stop()
     var
+        Venue: Record "Escape Room Venue";
         EscapeRoomNotifications: Codeunit EscapeRoomNotifications;
         EscapeRoomTelemetry: Codeunit "Escape Room Telemetry";
+        VenueCompleted: Boolean;
     begin
-        if Rec.Status = Rec.Status::InProgress then begin
-            Rec.Status := Rec.Status::Completed;
-            Rec."Stop DateTime" := CurrentDateTime();
-            Rec.Modify();
-            Commit();
-
-            EscapeRoomNotifications.RoomFinished(Rec);
-            EscapeRoomTelemetry.LogRoomCompleted(Rec);
+        if not LockAndRefresh() then exit;
+        if Rec.Status <> Rec.Status::InProgress then exit;
+
+        Rec.Status := Rec.Status::Completed;
+        Rec."Stop DateTime" := CurrentDateTime();
+        Rec.Modify();
+        Commit();
+
+        EscapeRoomTelemetry.LogRoomCompleted(Rec);
+
+        VenueCompleted := OpenNextRoom();
+
+        EscapeRoomNotifications.RoomFinished(Rec);
+        if VenueCompleted then begin
+            Venue.Get(Rec."Venue Id");
+            EscapeRoomNotifications.VenueFinished(Venue);
         end;
     end;
 
+    /// <summary>
+    /// Re-reads this room from the database while taking an update lock on its row, so that
+    /// concurrent sessions serialize on the status transition instead of both performing it.
+    /// </summary>
+    local procedure LockAndRefresh(): Boolean
+    var
+        Found: Boolean;
+    begin
+        Rec.ReadIsolation := IsolationLevel::UpdLock;
+        Found := Rec.Find('=');
+        Rec.ReadIsolation := IsolationLevel::Default;
+        exit(Found);
+    end;
+
     procedure GetHint()
     var
         TaskRec: Record "Escape Room Task";
diff --git a/non production apps/EscapeRoomApp/Src/3.Task/EscapeRoomTask.Table.al b/non production apps/EscapeRoomApp/Src/3.Task/EscapeRoomTask.Table.al
index 3e794eb6..dc7a145b 100644
--- a/non production apps/EscapeRoomApp/Src/3.Task/EscapeRoomTask.Table.al	
+++ b/non production apps/EscapeRoomApp/Src/3.Task/EscapeRoomTask.Table.al	
@@ -107,14 +107,27 @@ table 73922 "Escape Room Task"
         EscapeRoomNotifications: Codeunit EscapeRoomNotifications;
         EscapeRoomTelemetry: Codeunit "Escape Room Telemetry";
     begin
-        if Rec.Status = Rec.Status::Open then begin
-            Rec.Status := Rec.Status::Completed;
-            Rec."Stop DateTime" := CurrentDateTime();
-            Rec.Modify();
-            Commit();
+        // Re-read under an update lock: task completion is often triggered from event subscribers
+        // that fire in several sessions at once (e.g. the concurrency simulations).
+        if not LockAndRefresh() then exit;
+        if Rec.Status <> Rec.Status::Open then exit;
 
-            EscapeRoomNotifications.TaskFinished(Rec);
-            EscapeRoomTelemetry.LogFinishedTask(Rec);
-        end
+        Rec.Status := Rec.Status::Completed;
+        Rec."Stop DateTime" := CurrentDateTime();
+        Rec.Modify();
+        Commit();
+
+        EscapeRoomTelemetry.LogFinishedTask(Rec);
+        EscapeRoomNotifications.TaskFinished(Rec);
+    end;
+
+    local procedure LockAndRefresh(): Boolean
+    var
+        Found: Boolean;
+    begin
+        Rec.ReadIsolation := IsolationLevel::UpdLock;
+        Found := Rec.Find('=');
+        Rec.ReadIsolation := IsolationLevel::Default;
+        exit(Found);
     end;
 }
\ No newline at end of file
diff --git a/non production apps/EscapeRoomApp/Src/Telemetry/EscapeRoomTelemetry.Codeunit.al b/non production apps/EscapeRoomApp/Src/Telemetry/EscapeRoomTelemetry.Codeunit.al
index 79519b36..e7534970 100644
--- a/non production apps/EscapeRoomApp/Src/Telemetry/EscapeRoomTelemetry.Codeunit.al	
+++ b/non production apps/EscapeRoomApp/Src/Telemetry/EscapeRoomTelemetry.Codeunit.al	
@@ -97,6 +97,86 @@ codeunit 73925 "Escape Room Telemetry"
             );
     end;
 
+    /// <summary>Log a custom telemetry event scoped to a task. Standard task/room/venue dimensions are added automatically.</summary>
+    procedure LogCustomEvent(var EscapeRoomTask: Record "Escape Room Task"; EventId: Text; EventMessage: Text; ScorePoints: Integer)
+    var
+        ExtraDimensions: Dictionary of [Text, Text];
+    begin
+        LogCustomEvent(EscapeRoomTask, EventId, EventMessage, ScorePoints, ExtraDimensions);
+    end;
+
+    /// <summary>Log a custom telemetry event scoped to a room. Standard room/venue dimensions are added automatically.</summary>
+    procedure LogCustomEvent(var EscapeRoom: Record "Escape Room"; EventId: Text; EventMessage: Text; ScorePoints: Integer)
+    var
+        ExtraDimensions: Dictionary of [Text, Text];
+    begin
+        LogCustomEvent(EscapeRoom, EventId, EventMessage, ScorePoints, ExtraDimensions);
+    end;
+
+    /// <summary>Task-scoped custom event with additional caller-provided dimensions.</summary>
+    procedure LogCustomEvent(var EscapeRoomTask: Record "Escape Room Task"; EventId: Text; EventMessage: Text; ScorePoints: Integer; ExtraDimensions: Dictionary of [Text, Text])
+    var
+        CustomDimensions: Dictionary of [Text, Text];
+    begin
+        GetCustomDimensionsForTask(EscapeRoomTask, CustomDimensions);
+        AddScorePoints(CustomDimensions, ClampScorePoints(ScorePoints));
+        AddCustomEventDimensions(CustomDimensions, EventId);
+        MergeExtraDimensions(CustomDimensions, ExtraDimensions);
+
+        this.LogMessage(
+                'EscapeRoomCustomEvent',
+                EventMessage,
+                CustomDimensions
+            );
+    end;
+
+    /// <summary>Room-scoped custom event with additional caller-provided dimensions.</summary>
+    procedure LogCustomEvent(var EscapeRoom: Record "Escape Room"; EventId: Text; EventMessage: Text; ScorePoints: Integer; ExtraDimensions: Dictionary of [Text, Text])
+    var
+        CustomDimensions: Dictionary of [Text, Text];
+    begin
+        GetCustomDimensionsForRoom(EscapeRoom, CustomDimensions);
+        AddScorePoints(CustomDimensions, ClampScorePoints(ScorePoints));
+        AddCustomEventDimensions(CustomDimensions, EventId);
+        MergeExtraDimensions(CustomDimensions, ExtraDimensions);
+
+        this.LogMessage(
+                'EscapeRoomCustomEvent',
+                EventMessage,
+                CustomDimensions
+            );
+    end;
+
+    local procedure ClampScorePoints(ScorePoints: Integer): Integer
+    begin
+        if ScorePoints < -5 then
+            exit(-5);
+        if ScorePoints > 5 then
+            exit(5);
+        exit(ScorePoints);
+    end;
+
+    local procedure AddCustomEventDimensions(var CustomDimensions: Dictionary of [Text, Text]; EventId: Text)
+    begin
+        EventId := EventId.Trim();
+        if EventId = '' then
+            EventId := 'Unspecified';
+        if StrLen(EventId) > 80 then
+            EventId := CopyStr(EventId, 1, 80);
+
+        CustomDimensions.Add('EventId', EventId);
+        CustomDimensions.Add('EventSource', 'Custom');
+    end;
+
+    local procedure MergeExtraDimensions(var CustomDimensions: Dictionary of [Text, Text]; ExtraDimensions: Dictionary of [Text, Text])
+    var
+        DimensionKey: Text;
+    begin
+        foreach DimensionKey in ExtraDimensions.Keys() do
+            if not CustomDimensions.ContainsKey(DimensionKey) then
+                CustomDimensions.Add(DimensionKey, ExtraDimensions.Get(DimensionKey));
+    end;
+
     local procedure GetCustomDimensionsForRoom(var Room: Record "Escape Room"; var CustomDimensions: Dictionary of [Text, Text])
     var
         Venue: Record "Escape Room Venue";
diff --git a/non production apps/EscapeRoomApp/app.json b/non production apps/EscapeRoomApp/app.json
index 73cf2916..1bc7963d 100644
--- a/non production apps/EscapeRoomApp/app.json	
+++ b/non production apps/EscapeRoomApp/app.json	
@@ -2,7 +2,7 @@
   "id": "f03c0f0c-d887-4279-b226-dea59737ecf8",
   "name": "BCTalent.EscapeRoom",
   "publisher": "waldo & AJ",
-  "version": "1.3.10026.4",
+  "version": "1.4.1.0",
   "brief": "",
   "description": "",
   "privacyStatement": "",