Here's a hint that is hopefully non-spoilers: The first step is very unintuitive. After you place the first step, your immediate instincts will be "this is obviously wrong", but it's actually the right step. The second step will be the "aha moment".
Puzzle 4 is the boxbox one. I'm still not seeing it. Maybe it's a sign that it's stumping me but it feels like there are at most two moves that aren't obviously wrong.
