Fun c-cube map. Nothing difficult as most of these aren't, but I liked this one much better than most. Nice variation and creativity.

Very fun little companion cube map. Though I had the same problem as Mumalot, losing the cube and having to restart once or twice. The rest seemed fine, though the end was tricky. I had to look very closely at the signage before I realized I could just hold the cube on the wall button to get the beam reversed.

A nice collection. The passage leading to the tractor beam was nearly invisible in the dark — if you don't intend it to be hidden then a little more light in that area might be good.

Yeah, you have to be careful not to get your cube stuck under the moving tiles. When I first made it I had the 2x2 elevator activator on the other side and when I kept returning for the cube I would accidentally put it under the elevator trying to walk around it.
Try to drop the cube directly into the receptacle for the lift so it doesn't bounce out.
As far as the ramp, I'm not even totally sure how you got the cube under it haha. after you drop the gel and run up the ramp, use the beam around the corner to pull the cube toward it. You never have to get the cube near the ramp.

looks like a nice puzzle, but I keep killing my cube somehow... seems like it just vanishes if its in the way of any movingtiles.

I've had it died on the 2x2 elevator, it bounced off the pad near the elevator and poofed when it went on to it.
And it died again on the angled ramp that you need to speed-gel up.