Hahah, I just went and played through the game again to try and work out what stumped me so much on that level (it might be ten actually? The one where you have to hook the valve over from one chimney to the next) and blazed through the whole game in less than 5 minutes. So your setup to teach the rules of the game is working really well. I think the thing that made that tricky was the step to visualise a tool for extraction as well as the solution. Earlier you've got to figure out the final shape but this one is the first where you have to do two things with your shape.
Again, this is very cool and I had a lot of fun blasting through a second time.