So, if I understand correctly, the amount of monitors connected, and the relationship to the 'main' monitor (having the start-button) makes such an impact, you get an Apphang? Ok, that is something different.
Hopefully the guys at D-Link can find out what happened, but this points them in the right direction. If they now would also make the screens moveable and not use full-screen (2.04+ had that option, but would skew ratio displayed on screen), we would be helped out. I was planning to go multi-screen as my card "only" supports 2 monitors, but thanks for finding this out.