- adding "resolution switch 0" to either config file
That should work when added to the config.div file. Did you add it at the very end? The game expects the last like to be blank, and ignores it, so hit enter before saving.
That was the issue with the fix... config files are very sensitive animals!
Now I'm getting a similar error "can't reset gfx" upon alt-tabbing (on the main menu as well). I'll try out your other suggestions and see if it works, but at least now I can move on in my game.