Thought I'd post about this somewhere. We did an update earlier and it introduced some fixes to some of the problems you've been talking about. Now for example you can't crash with a rotation bug anymore, stacking should be completely consistent (the problem you were having where items would fall to the bottom was interesting, because if you left your room for more than five seconds instead of reloading the problem wouldn't even be there! provided noone else was in the room that is).
I've also made it so you can't place things on varying heights... this might be unwelcome for some, but it's for the best. I've also decreased the item limit, but it had to be done, in rooms that aren't just pixels the old one was causing so many glitches (most likely due to shockwave running out of sprite channels).