Something else that may have happened, is something is not in the correct file. If you were trying to download something, or export something, it may have gotten moved to the wrong file.
This may sound crazy, but delete your entire exports folder, then re-install FeralHeart. This has happened to me numorous times, and that is all I could do.
Also, if you put anything in your FH that has a material file of some sort (like a preset) make sure that is all correct. Sometimes, having the wrong file in a material will crash it.