The only places I died are 1-3, 1-4, 2-2, and 3-3. 5-2 is difficult. After you get the key, wait 1/2 the fall and then jump. After that, keep jumping - your weight slows it down. If you manage to do it with enough momentum, you can make it. If not, keep trying.
Am I the only one who did level 10 without help? Level 11 is the one I struggled with, though the video showed I was VERY close- just a few swaps to fix it.
Because we forgot to change it ;)