When I try to add a transition or effect in 12 and the Plug-In Chooser window has to open all I get is an empty, blank white window. I have restarted the computer 3 times to no effect. I also uninstalled and reinstalled the program with no result. I also have Vegas Movie Studio HD Platinum 11.0 and it's working perfectly fine. The problem is only with Movie Studio 12.
I have Sapphire Edge and NewBlue which I also uninstalled to see if they were the problem but it still doesn't work. And the program just started doing this with no change in the system. I had been working on a project for a few hours with no issues when suddenly I couldn't add transitions.

Please help. The program is pretty much unusable to me right now.