Simple, but a nice tech demo all the same - reminds me a lot of Tricky Towers. Physics stuff is always a nice surprise and I was happy to discover this one =)
I did find the question mark shapes to be a little difficult to deal with. Nice twist, it's just that I had absolutely no idea where to place them because it could turn into any shape at all. The hard-reset bug was also frustrating, but I think you know about that one already, lol.