I had an issue with what I thought was Vegas. Nope. I was getting cursors that I couldn't place and regions being made willy-nilly. Ugh . . . OK, thinking back to a similar situation I had with my keyboard, a sticky shift key, I went through and by a method of elimination it appeared to be a mouse click not being "taken" - time for a new mouse. Now, in all this elimination I disconnected all my USB pointers - KB, mouse, graph pad AND my CSP.
Just thought you could "file" this as another non-Vegas issue.
Maybe that would be useful:
"I thought it was Vegas, but actually it was.... "
Time for a new rodent?
Grazie