Game crashes randomly

[SheepRider]

Hi,

I've bought the game today on Steam and every time I try to play it, it crashes randomly: The game stops, sound loops for a couple of seconds, then the screen goes black, then a white window appears with the "loading"-mousesymbol. After a while, the classic windows-crash-warning appears (no response, you can wait or close etc.). It never happens at the same point, and always during a level.

I checked the troubleshooting already, verified the game-cache, tried different settings and got the latest AMD-update, but nothing helped.