Very nice entry. I like the visuals and music but control is kind of confusing to be honest :). I don't know why you decided to use Z to jump. I think spacebar would be a lot more comfortable.
And what is the purpose of allowing arrow controls? If Z is the only button to jump then it's impossible to fully control the character because you still have to use a mouse :D.
Apart of the controls, it's a solid game. Thanks!