Thank you for the bug report. You're right about the "hear clip again" button being greyed out. I hadn't even noticed that until now, and I'll have to see why loading a dub session does that...
Is the crashing in 0.5.3 more common than previous versions for you? I really wish I knew why the game is fully playable for some people, yet crashes constantly for others... I have yet to figure that one out. I'm sure it's really frustrating to deal with.