Very nice entry, I really enjoyed it. I loved music in the library and I think I'll hallucinate this library for quite a while now because of around 10 attempts before I finally beat it.
Hardest thing on the first level was that after you solve second puzzle (long corridor with switches) you actually need to know that you can pull switch from across one square, and you don't need to stand in the square next to it. Took me couple of attempts to figure that out (by accident) and then had an "aha" moment.
Time pressing is brutal, especially in the second level, where you need to remember all the rotations and build a mind map in the head, but any slight mistake will lead to a failure. I was surprised to find a time reset by the end (by accident).