I doubled clicked an event by accident and now there are two sub-tracks "A" & "B" on one track with an "X" in between. Also one of the events is now grayed out and I can't edit it. 16 levels of Undo doesn't set it back to what it was before. Any ideas?

Doesn't matter now - just lost nearly two hours of work...Never - in nearly 14 years of using Vegas - has the program been so broken...