Pretty cool game.
Reminds me of Icy Tower

My suggestions though :
-Add a random mode, which randomly put stuff around, kind of an infinite mode.
-Have some kind of static scrolling...? Sometimes you jump, think you'll fall on a platform, but the stage scroll so you die =/
-Enable character on the top screen, would be really cool ^^
-Different randomly picked sound, boing-boing-boing can be annoying, haha.
Good luck in the contest ! You have a good game there, and you can still improve, don't you think ?
By the way.
I read a bit on your blog. Don't worry about switching from PaLib to Libnds. There are a lot of things I still don't understand, but it is WAY better ^^
I tried to used PaLib to do some kind of a RPG using 3D functions of PaLib, and got discouraged cause of bugs and feature lacking. I now know I can do it with libnds.
Don't stop making games, you'll like the switch. Just an advice from me, hehe =D