AGS: Unknown variant result in "data not found" when running game
The problem can be seen for game variants we don't yet have explicit detection entries for, such as for Tale of Lonkey Island found here: https://www.adventuregamestudio.co.uk/site/games/game/2100-the-tale-of-lonkey-island/
When the game is added, two targets appear: one for Lonkey Island Unknown Variant, and one for the generic AGS game Unknown Variant. If you add the game using the Lonkey Island Unknown Variant, then thereafter, the game won't run.
The problem seems to be in the fallback detection code. When the game is run, the only fallback entry found is the generic "ags" one. But there's code in the base advanced detector that ignores it, since the entry in the config file has a different game Id of "lonkeyisland" than "ags".