Fully customized game profiles (select any WAD as IWAD)
The user should have the ability to pick any WAD file as the IWAD of a game profile, bypassing the engine's automatic detection. This also requires that the user selects the game mode (e.g., "doom1-ultimate") manually.
UI|Home|Resources: Custom data file in game profiles
Starting a profile with custom data file doesn’t work yet because the game plugin’s required PK3 isn’t being automatically loaded either.