Hey, if you could send us a file called ouput.log to us either here or on facebook we can try and locate the problem.
The file can be found in the Data folder which is located next to you executable file.
Thanks!
Sorry i couldn't send you the file cause it contains some personnal info but i found this in it.
d3d11: failed to create vertex buffer of size 116640 [0x887A0005]
d3d11: failed to create index buffer of size 5556 [0x887A0005]
d3d11: attempt to lock null vertex buffer
d3d11: attempt to lock null index buffer
the last two lines repeat almost endlessly in the file so I thought it was the bug. I hope it helps you improve the game and thanks for answering me. (I have a GTX 560 Ti in case it has to do with the graffic card.)