Bumptop not starting correctly in Vista, no error messages.

When I click "Show Bumptop" all that happens is that all of the icons on my normal desktop disappear. I am left with the taskbar and my wallpaper. The only way to restore my icons is to quit Bumptop. Bumptop doesn't appear to be crashing because I can still right click the tray icon and quit, no problem. I haven't seen any error messages. I have never seen the actual 3D bumptop yet. What could be causing this?