Changing the graphic itself wouldn't change anything. The problem appears to be in the routines that display the loading screen, and the fact that it clears when you toggle the screen points to something in the graphics chain.My best guess is that it's a problem with DirectX 10. I presume that you have the most recent version and I wouldn't expect Microsoft or Ubisoft to care much about fixing the problem.
You might try fiddling with the DirectX settings by Disabling and Enabling the DX Features under the Display tab of DxDiag. I'm betting that it won't help, but there no harm in trying. You can also make sure that the drivers for your graphics card are current. Please keep us informed. Thanks.
