Ok, so I just downloaded FTB tonight, and went to create a new world. It took a while for the world to be created, and it didn't even open, it just went back to the main menu. I went back to single-player and the world I had tried to create was there so I tried to open it. It loaded for a while until it crashed. I tried this again with the same exact result. Thanks very much if you can help. Feel free to ask questions if you need further information. 