buttons to open the door.
test 8 (2:58) - climb on the middle-right platform and walk to the right, you will find the key there.
test 9 (3:20) - go back to the previous level and take the key again from the secret room.
test 10 (3:45) - press the buttons in this order: middle-left, bottom-right, bottom-left, top-left, middle-right, top-right.
test 11 (4:30) - you can break the platforms with your head, start by jumping where the arrow points, then left side, then right side.
test 12 (4:55) - you have to go back to level 11 and walk into the right wall, on each platform. you will go into level 12 and be able 