Cinema viewer mode locks up when trying to exit beta5

When I switch to Cinema Viewer mode it works fine but if I try to get out of it while a clip is playing, it will continue playing fullscreen, and I get a dark gray frame around the entire screen, with some unrelated controls showing, like the Qualifier highlight, which don't do anything when clicked. The only way to get out of this is to open Task Manager and shut down the program. The esc key does nothing.

Just a heads up to the Bug Team.

I just installed the beta 5 and have the same issue.