I've also have the game.. And I've finnish that out.
The freezing problem is a bug. Go to the official homepage for the game and read more about it.
Try to istall the 1.1 patch!
And the freezing part are a random bugg what I know about.
My game has only freeze one time. And quit by there self 2 times. So there is a random bugg. But however... there are some fixes in the 1.1 patch. But not much. Game has crash 1 time after I install the patch but not crash, yet..