In my case if you don't run the game as administrator the game opens in a black screen then freezes and it won't close with alt-f4 it must be closed with the task manager. Small bug but still if you don't think about it you may be sitting there awhile trying to figure it out. And of course the frame rate is ridiculous i get anywhere from 5-60 fps. Specs: OS Version: Microsoft Windows 8.1 Pro 64-BitSystem RAM: 16354 MBCPU Name: AMD FX-8350 Eight-Core ProcessorCPU Speeds: 4700Physical CPUs: 1Virtual CPUs: 8Video Card Description: NVIDIA GeForce GTX 660 TiVRAM: 2048 MBPrimary Display Resolution: 1920x1080Multi-Monitor Desktop Resolution: 5760x1080