It works like last time: there is a whole new world with 12 NEW PUZZLES, but hidden. To unlock that world you have to LOSE the first level. "Try again" must appear on the screen when you lose. Once that happens you will hear the victory music. Go to the map and the new world will be unlocked.
If you want a tip in how to do that: keep poking the gray toad (lots of pokes).
I'm looking for feedback on those levels mostly, the rest of the game is pretty much the same, with the exception of the demo end.