[Nouveau Graphic Driver]Crusader Kings 2 does not works

[Berillions]

Hi,

I tried to launch this game with the open source driver for my Nvidia graphic card and not with the non-free driver.

With the non-free driver, the game runs correctly without problems but with Nouveau, i have a black screen during the first loading and after. I have only the sound's and cursor's game.

I run Steam Linux on Debian Wheezy, the "libgl1-mesa-dri-experimental" is installed.
So, if someone has tried to play at this game with Nouveau and if it's works, thanks to help me.

I post the pastebin for the error message in the error.log file :
Pixel/Vertex Shader Problems[pastebin.com]