My only complaint is that the double jump is a little to touchy and it's fairly easy to accidentally hit that extra jump when you don't mean to. That and I wanted more, as I was just getting into the story. I look forward to the full game once it's fully funded, and I hope it truly does. It has so much polish and promise.
P.S I realized I had played one of your previous titles The Littlest Penguin, and that was a blast as well. I put this up as one of my Showcases for developers. Everyone I do recommend this, and not because I was reached out to, but because this demo is incredibly polished, and was so much fun to play.