I'm not sure if you've already tried this.
Go to FeralHearts -> media -> particles
If there are any files there that have a _0 or a _1 behind them. Delete them and see if the game works.
Nope, there's not any file with '_0' or a '_1' behind them.. but, all of sudden, my game is working again. adoajiodwa. Sorry for causing all of this trouble, though. I reinstalled it again just in case, so it wouldn't give me any more trouble. Thanks for all the help. <3