I really like that you made a momentum-based platformer. It feels like you gave this game a lot of character that helps it stand out in a sea of overly derivative platformers that do nothing new. I'm sure you know the game has issues, but you didn't list the game as a demo or anything so it seems kind of misleading. You set up a story about an energy source for Planet Plum but then the game unceremoniously ends after beating a boss we know nothing about. Are you intending to continue working on the game at all?
I don't mind the momentum mechanics normally but Platform Panic feels very strange when you're riding the moving platform because you don't maintain any of the platform's momentum. You jump and then immediately stop moving forward like there was an anchor holding you back.
Also, it seems like the levels should keep a record of whether you've collected the stars or completed the bonus portals.