I really like this game! The mood is well-made, the music is awesome and doesn't get boring. The cutscenes and the colors help a lot. The graphics are simple but beautiful, and the difficult is very balanced as you go through the levels. The very single bug I found is that, when you jump to a platform above your height, you can jump just after touching that platform and perform a REALLY big jump. Maybe its just part of the game mechanics, and not a bug itself.
Anyway, nice job! I am eagerly waiting for the second part!