I think my best so far is to make it to the 10th. As a general question for any puzzle, it sometimes seems as though multiple solutions should work on the first line, but it's looking for one specific solution. Is that correct, and if so, is it just trial and error to get that right sometimes, or am I missing something?
I like the story (both on here and in-game), but honestly I've tended to skip over it once I get going. I'd suggest some images or more detail in the text, but what's there makes sense given the minimalist nature of the game.
That said, I'm having trouble getting into the final room of world 3-3. There is no path to the door on the right, and the path from the bottom is inaccessible even though it appears to be an open, normal path. It doesn't allow you to go up to enter the room. Am I missing something?