The general experience was quite great.
You have a nice menu and great graphics/ music.
The level them self felt a little short lived and level 6 is a bit hard to understand.
For some platforming advice I'd suggest to make the space in which you can jump a bit larger. I had moments standing on the edge of a platform and couldn't jump.
Beside these, I think the game I great and that you but in 6 secrets is a real plus.