Hi, I think I have the same problem.
I have Win 7 x64. After installing the drivers in the cd, some things don't work, like the panel to change the screen resolution, or the properties window of "my computer", or even programs like winrar stopped working.
I had some new custom drivers compressed in a file I downloaded from here:http://brainbit.wordpress.com/2010/07/19/asus-xonar-unified-drivers/
But as winrar didn't work I couldn't install them. I will try them later when I manage to extract them.