I am on Windows. I appreciate anything that could take me out of this unfortunate situation.
I can fully understand how you feel, I've been in the same situation, but moreover one of my app was a paid app, so people got very angry since they payed, played for a while, then I had the brilliant idea of update the app so the ended up with a black screen... Luckily I always keep older Stencyl builds, so I could revert quite quickly.
Maybe you can ask on discord if anybody has an older build, people seems more active there.
By the way, for your second question, I've posted in the issue tracker, updates should appear in this post
http://community.stencyl.com/index.php?issue=1996.0