I have exactly the same problem. I'm using x64 - Windows 8.1. The output_log.txt has plenty of problems concerning the database:
<lots more of the following has been deleted>
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Fallback handler could not load library I:/xxx/Demos/Robbing HUD/Robbing HUD/RobbingHUD_Data/Mono/sqlite
Fallback handler could not load library I:/xxx/Demos/Robbing HUD/Robbing HUD/RobbingHUD_Data/Mono/.\sqlite
Fallback handler could not load library I:/xxx/Demos/Robbing HUD/Robbing HUD/RobbingHUD_Data/Mono/sqlite
Fallback handler could not load library I:/xxx/Demos/Robbing HUD/Robbing HUD/RobbingHUD_Data/Mono/libsqlite
Fallback handler could not load library I:/xxx/Demos/Robbing HUD/Robbing HUD/RobbingHUD_Data/Mono/.\libsqlite
Fallback handler could not load library I:/xxx/Demos/Robbing HUD/Robbing HUD/RobbingHUD_Data/Mono/libsqlite
Fallback handler could not load library I:/xxx/Demos/Robbing HUD/Robbing HUD/RobbingHUD_Data/Mono/.\I:/xxx/Demos/Robbing HUD/Robbing HUD/RobbingHUD_Data/Plugins/sqlite3.dll
Fallback handler could not load library I:/xxx/Demos/Robbing HUD/Robbing HUD/RobbingHUD_Data/Mono/.\I:/xxx/Demos/Robbing HUD/Robbing HUD/RobbingHUD_Data/Plugins/sqlite3
Fallback handler could not load library I:/xxx/Demos/Robbing HUD/Robbing HUD/RobbingHUD_Data/Mono/libI:/xxx/Demos/Robbing HUD/Robbing HUD/RobbingHUD_Data/Plugins/sqlite3.dll
Fallback handler could not load library I:/xxx/Demos/Robbing HUD/Robbing HUD/RobbingHUD_Data/Mono/.\libI:/xxx/Demos/Robbing HUD/Robbing HUD/RobbingHUD_Data/Plugins/sqlite3.dll
Fallback handler could not load library I:/xxx/Demos/Robbing HUD/Robbing HUD/RobbingHUD_Data/Mono/libI:/xxx/Demos/Robbing HUD/Robbing HUD/RobbingHUD_Data/Plugins/sqlite3.dll
DllNotFoundException: I:/xxx/Demos/Robbing HUD/Robbing HUD/RobbingHUD_Data/Plugins/sqlite3.dll
at (wrapper managed-to-native) Mono.Data.SqliteClient.Sqlite:sqlite3_open16 (string,intptr&)
at Mono.Data.SqliteClient.SqliteConnection.Open () [0x00000] in <filename unknown>:0
at SQLConnection.DatabaseConnection (System.String _dbFilePath, System.String _sql) [0x00000] in <filename unknown>:0
at SQLDataRetriever.RetrieveSLQData () [0x00000] in <filename unknown>:0
at SQLDataRetriever.Awake () [0x00000] in <filename unknown>:0
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The strange thing is that the dll from the bold error message is actually there, and it is the 64-bit version (the exe was 64bit as well). I was using a version of your program where the .exe was from 08/10/16
If I can help solve the issue, contact me at ingowarnke@gmx.de.