I used to get white screens and display when using Moi V2.
I found that when I was using a classic windows theme - trying to get windows to use open GL drivers rather than direct x - Moi would have display problems including white viewports.

If I change to an Aero theme - Moi works with no problems, but my other CAM software that needs open GL has display issues.

Not sure if I am right, but thought it might help someone