Thanks Art.
Before the last release I spent hours and hours testing -- full run-throughs on 3 computers, top to bottom, playing all the scenes and killing the player here and there. I tested windowed, then full screen. I always spot a few things that I think are enough to fix. It must be re-done many times. I'd say it takes about a day and a half, though I take lots of breaks. It's tedious.
None of the show-stopping bugs can be reproduced on my end. I don't get the dropped mouse button. It doesn't exit during start-up. I'm taking a little break while I look for a replacement for SDL. I've seen complaints that it doesn't work with nvidia, and that it can spontaneously fail. I'm a bit worried that the other free front-ends might all be in a similar state.