A lot of people have problems with the jumps in the game and in particular with this level.
So i found something i wanted to share, that helped me alot with this level.
The platforms the keys are on, all have the same layout.
I made a sketch that shows it: http://imgur.com/a/nGcL3
What helped me was:
1. I always jumped from the "O"positions, never from the "X" ones.
2. Picked up the key,
3, Looked down and ran straight to the next circled area ahead
4. Jumped at the point of the "triangle".
As soon as i started doing it this way, i never failed a jump.
Hope that helps a few people out there !