Hi, I had the controsl problem on the embedded but it worked fine on the dropbox link. Pretty cool, but lacking in some UI imho, like a gauge to show you how strong your jump is going to be. Also, you should reset the player speed when respawning, because it makes it harder to understand when you die and insta-respawn flying. Anyways, pretty cool :) Nice music also!
I had trouble getting the game to work; it seemed like when the rainbow collided with the chicken the game threw a bunch of errors. (This was in the web version.) By the way, I think you need to link to the HTML file in your Dropbox so the user doesn't have to download a zip. Nevertheless, the graphics are really cheeky and adorable, and I love making the rainbows! Great concept.
Runs fine on Linux under Wine, and I love the art style. The game could use WASD controls as well, though; You can only right/left with SD, while you can also jump with the arrow keys.
Just a heads up, I don't think compo entries are allowed to use premade music. Jam entries can, however. Sorry if I misunderstood what you meant.
I got stuck behind a tree when landing on a platform. Also, trees don't seem to count as platforms so the rainbow did not reset.
The jumping is kind of fun, but I feel like it needs to charge faster and there should be some sort of visible indication when you reach max so you know how long to hold the button down.
I think you can change your category to "jam" instead of "compo" by the way. A lot of compo games don't even have music because people run out of time.
Anyways, pretty cool :) Nice music also!