Excellent game you got here.
Obviously, the art style and the plot mix together very nicely. I don't even see how people can compare this to games like Limbo. Might as well argue every colored game is derivative of each other.
It's just challenging enough to engage, while not being too frustrating. Was a bit stumped for a few minutes at around level 23 or 24. But figuring these things out feels really rewarding.
I admit, I wish the platforming was a bit more forgiving (jumps not registering when falling an inch on an incline).
As for the music, I never felt it got in the way. In fact it actually added to the overall eerie atmosphere of the game.
On the other hand, the ending could've needed a bit more closure. Pun wholly intended. :)