Level 4 Hint
What direction do you need gravity to be in to the reach the exit? Which level can change gravity to be in that direction, and and what states can you leave that level in?
Level 4 Hint #1You need to somehow press the gravity shift button on another level, being on the 4th Level 4 Hint #2Gravity affects the character in all open levels. By changing gravity, you can move your character not only on the current level, but also on any open level.