This build is pretty stable, I agree, but there's one thing that's desperately in need of a hotfix. The collision bug still stands, and I'm making a cap right now to prove it. Collision accuracy is one of the most important features in construct, and having a bug this bad is enough to make me hope that this build is going to get hotfixed sooner than later.
edit:
<img src="http://files.getdropbox.com/u/1010927/Colbug.png">
GET THE CAP HERE: http://files.getdropbox.com/u/1010927/S ... Tester.cap
You may have to relaunch the runtime multiple times for the bug to appear.