Fixed.

The issue was dbo.SceneCharacter_Save being stored with QUOTED_IDENTIFIER off, which SQL Server rejects when inserting into tables involved with filtered-index requirements.

PlotLine/Sql/099_FixSceneCharacterSaveQuotedIdentifier.sql

@@ -0,0 +1,52 @@
+SET ANSI_NULLS ON;
+GO
+SET QUOTED_IDENTIFIER ON;
+GO
+
+CREATE OR ALTER PROCEDURE dbo.SceneCharacter_Save
+    @SceneCharacterID int = NULL, @SceneID int, @CharacterID int, @RoleInSceneTypeID int = NULL, @PresenceTypeID int = NULL,
+    @LocationID int = NULL, @EntryLocationID int = NULL, @ExitLocationID int = NULL,
+    @AppearanceNotes nvarchar(max) = NULL, @OutfitDescription nvarchar(max) = NULL, @PhysicalCondition nvarchar(max) = NULL,
+    @EmotionalState nvarchar(max) = NULL, @KnowledgeNotes nvarchar(max) = NULL
+AS
+BEGIN
+    SET NOCOUNT ON;
+
+    IF @SceneCharacterID IS NULL OR @SceneCharacterID = 0
+    BEGIN
+        SELECT @SceneCharacterID = SceneCharacterID
+        FROM dbo.SceneCharacters
+        WHERE SceneID = @SceneID AND CharacterID = @CharacterID;
+    END
+
+    IF @SceneCharacterID IS NULL OR @SceneCharacterID = 0
+    BEGIN
+        INSERT dbo.SceneCharacters (SceneID, CharacterID, RoleInSceneTypeID, PresenceTypeID, LocationID, EntryLocationID, ExitLocationID,
+            AppearanceNotes, OutfitDescription, PhysicalCondition, EmotionalState, KnowledgeNotes)
+        VALUES (@SceneID, @CharacterID, @RoleInSceneTypeID, @PresenceTypeID, @LocationID, @EntryLocationID, @ExitLocationID,
+            @AppearanceNotes, @OutfitDescription, @PhysicalCondition, @EmotionalState, @KnowledgeNotes);
+
+        SET @SceneCharacterID = CAST(SCOPE_IDENTITY() AS int);
+    END
+    ELSE
+    BEGIN
+        UPDATE dbo.SceneCharacters
+        SET SceneID = @SceneID,
+            CharacterID = @CharacterID,
+            RoleInSceneTypeID = @RoleInSceneTypeID,
+            PresenceTypeID = @PresenceTypeID,
+            LocationID = @LocationID,
+            EntryLocationID = @EntryLocationID,
+            ExitLocationID = @ExitLocationID,
+            AppearanceNotes = @AppearanceNotes,
+            OutfitDescription = @OutfitDescription,
+            PhysicalCondition = @PhysicalCondition,
+            EmotionalState = @EmotionalState,
+            KnowledgeNotes = @KnowledgeNotes,
+            UpdatedDate = SYSUTCDATETIME()
+        WHERE SceneCharacterID = @SceneCharacterID;
+    END
+
+    SELECT @SceneCharacterID;
+END;
+GO