I found this to be a really relaxing and enjoyable experience. The original art is really charming; reminds me of games like Rayman, which is always a plus. The puzzles are well designed without being convoluted or frustrating. I would definitely pay money for this.
If I had one gripe, it would be that the sound effects probably could be something other than generic 8-bit sounds. It doesn't really fit the style of the game. I think something more natural sounding would work a lot better.
Great work overall. I am looking forward to the final version!