Well, as far as i know, you can use Lua for UI effects as much as you want by overwriting core game files. You can also create "game scripts" that affects the game, but those are only loaded when you create a new game, and not when you load a saved game, making them useless for anything but initialization. Not sure whether it's a bug or there is something to add to the modinfo file. Somebody might even have found a way to load them with saved game but in this case, i missed the announcement. EDIT: Just asked. Both LeeS and Gedemon confirmed that gameplay scripts still don't work so currently Lua modding is very limited (mostly UI stuff and a few game affecting functions that might be hacked into an UI script) So there's no way to do it easily with modifiers is there?