Level 19 is supposed to be hard!
I, for one, thoroughly enjoyed this game. It's always fun playing a platformer with a neat new mechanic, and the respawning platforms definitely are a good one. I, like most of the others, was frustrated by level 19's difficulty, but level 20 reveals the genius of it: level 19 trivializes your death so much, that once you get to level 20 you'll dive for that easily accessible bonus coin in an instant, thinking that you'll respawn and just be on your way...The fact that after doing so resets the level select also helps illustrate the point that sometimes you only do have one chance, and if you blow it you have to work from the ground up (or it could be a bug and I'm overanalyzing things. Either way, my point still stands.)