C'mon guys, this game is not bad, I can see a potential in it. There are only few things that bother me:
1. You should add arrow keys controls;
2. Does the medal actually work? Did you test it by finishing the game?
3. If you will make the game too long, then - if the game won't be saving progress - there is a great risk that when somebody will actually finish it - won't be awarded, because the game will simply disconnect from Newgrounds before that.
4. As for what "100% Done" means: on one level I missed a tricky coin placed just next to the level exit - will all coins be also required for that medal?