I've been troubleshooting this for a while, and the only conclusion that I can come to is that it cannot find the game. I've changed the game directory in FAF to "/home/dankf/.steam/steam/steamapps/common/Supreme Commander Forged Alliance" which is where the exe for the game is, but it still doesn't work. Perhaps I have to make something the launches it through wine? I'm not sure.
Thanks, and if you need any more info, lemme know.