I liked the idea and the puzzle itself. Making the big lazer shape was fun.

Since the player shouldn't mess with the reflection cubes at the bottom (but I managed to get down there), I'd recommend you put glass all the way around the inside to keep the player out of there. If you want the player to walk down there but not move the cubes, maybe just place glass walls around the cubes and add more platforms so the player can walk around.

The antlines are a bit of a mess. I know how that is; it kind of sneaks up on you. Some of them are even going through the signs for other connections. In particular, the ones that go through the bridge in the middle are almost entirely unhelpful; I can't tell what they're doing. In fact, at several points I wasn't quite sure which connections could be removed. (Nuclear option: fix what you can in the puzzle maker, then export to hammer and just move things until it's how you want them.)

When actually aiming the second lazer throgh the portal across the room, I had to just blindly guess until I lined up the shot. It could be a bit less painful for the player if the flip-panel was on the same logic as the gate for that area. You could also consider moving the panel to the near corner of the room, but I'm not sure how that works out with the angles.

I hadn't read the description before I played, but it was a nice bit of text itself. Good flavor for the map.

I do like the look of the floating 'ufo' platforms. So yeah, great work!