Game is really tedious and even though the different difficulty settings offer some variety as far as a challenge goes, nothing gets harder in whatever mode you're playing on.
It takes forever to get the medals, and a lot of that has to do with the fact that the score seems kind of random as far as how it tallies itself up. I can only imagine that there's a hit test at the bottom of the screen below the canvas that registers it and deletes the movie clip while upping the score, but whatever it is it doesn't seem to work very well (actually, that way seems like the best way of doing things if you hadn't done that already).
Also, increase the frame rate. A game like this would work better if it was smoother looking, and 12 fps (or possibly lower) doesn't cut it. Makes the game feel choppy.