Good job on this game!
I did have some difficulty with the control of the character, the combination of the floaty jumps and slippery ground made it hard at times to land and stay on the narrow buildings. I also almost died a few times coming out of a portal with some velocity, almost sliding of the platform before I could move.
Sadly I wasn't able to finish the game, when I saw the girl standing at what I think was the end, I fell of the platform but couldn't move anymore when I got out of the portal.
I liked the contrast between the grey sad world and the happy colorful 'dreamworld'. The changes in music also really helped with that! The (changing) different gravity in was also a nice touch!