[PTI] Glassic 90
It's mostly 5 main chambers, but there's a few glass barriers within each. It's a bit of a thinker, especially the first part. There's tractor beams, light bridges and a laser at the last chamber, as well as some portal flinging. I'd put it at slightly above medium difficulty. I've also kept the elements down to a bare minimum considering all those glass barriers to avoid confusion or obscurity. I spent a few days on this because I want my 90th puzzle to be a good one. I hope you like it.
Well, I actually made it to the end. But I could not tell you how I did it. I was soooo confused for much of the time. I think the primary problem was that I could never be sure if my actions were actually getting me closer to the end or not, since you couldn't see it until you were almost there. Plus, you seemed to have some side chambers, which I think were to allow you to get back to the cube if necessary, because there were many things I just didn't use. I liked the difficulty and variety of the puzzles, but some kind of direction would have been nice. I know there is not much you can do in the editor, though.
Here is the route I found up to the laser room. I think I skipped more than you had intended. The laser room I think I did as intended.
EDIT: [Video deleted.]