I got the bug that doesn't let you buy things you have enough money for. The button is invisible, but it still can be found in the middle of the game's right edge.
Really really really needs to ask for confirmation in case you accidentally click 'clear all' in the Trophy Room; also, it's easy to cheat on the 'Use at least X pieces' challenges. Other than that, this is one of the best games I've played on Kongregate. Definitely 5/5
Magnificent game, original concept and great physics, definitely a 5/5. But there seems to be a little glitch: I could beat the last level by placing only one of the pieces on the red platform, instead of forming the entire puzzle.