As the person above me stated, yes it could be your graphics card. Or, another reason that happens is when you are copying everything into FeralHeart>Exports, maybe you didn't click "Copy and keep both files". (When it asked you I mean) If you don't keep both the files, the map usually wont work. So try redownloading, and Copy but keep both files. If that doesn't work, it probably is your graphics card. Good luck! ^^