There's a cheat for the last level, instead of perfectly timing everything, attach the 1st wooden piece to the lowest wooden piece, it will sink down, then attach the 2nd wooden pieces to the 1st wooden piece, before quickly attaching the 3rd. The wooden structure will fall, along with the Box.
Lol, i finished act 11 by just waiting for the action to die down. Go around the teacher, past her table, go at the windows side and cheat, moving upwards nearer the topmost window whenever her view goes leftward towards the geek. And moving nearer and cheating when her vision slightly shifts to the right. Just keep going up and down, up and down. Far simpler than any other solution.
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