Have quite finished now.
×1W: A nice easy room to start with.
1N1W: I'm pretty sure this is only possible from the West. I did have to print it out and draw paths to work out what to do.
2N1W: Counterintuitive is good.

2N: I did it from the South
2N1E: A nice invisibility optimisation problem.
1S1W: This took me longer than it should have done.
1S2W: Easy if you know how serpents work, probably somewhat frustrating if you don't. (heh heh heh)
2W: 10 square long grooves in the floor.
1N2W: I'm not sure what you intended, but I don't think I did it. :/
2N2W: Very nice.
3N2W: Nice.
3N: Very nice.
1N1E, 3N3E: Hrm.. the rooms aren't challenging. The scroll in 1N1E can be misinterpreted, which I'm guessing is the intention?
4N1W: A very nice room. Again, if you don't know how serpents move, you're may make the wrong choice. But then again, if you've done all the other rooms, you should hopefully have some idea.