The second puzzle is really engaging and hard. I spend like 10 minutes trying to figure out the puzzle. At first i was confused on what i have to do. But eventually it occurs to me on what you want me to do, although it was still not really clear how to make it possible.
After trial and error, and getting this to the "right" place (no spoiler lol). Then it was very very satisfying. Really cool concept! Too bad it doesn't have any audio or music :(