First off, Keep your Demos on your dumping grounds. Secondly, Get that "Feedback" Crap off of this. It causes my virus scanner to go all loopy.

Add more stuff.

The physics is good, and your game play is inventive (the blocks that suddenly begin moving all over the place).

but you made the game difficult right from the beginning, and i lost interest in trying to make it any further.

With no music, no sound effects and boring graphics, this isn't a game but is a homework assignment instead.