I'd suggest allowing bug reports directly from the app. You can capture highly useful context with the report. You have highly technical people here eager to help your wonderful creation!
To me it looked like a crash, but I do understand that programmatically it wasn't a "crash" or an unhandled exception.
2. Since this is a pre-alpha/alpha/beta version, there's nothing wrong with a green button with a picture of a bug anywhere in the interface. Just open a dialog explaining that although horrified, you'll be thrilled to learn of any bugs.