Nice to see the mechanic used again. Had a lot of problems in the first chamber, placing a blue portal anywhere caused the cube to jump off the button - then sucking it into the center made it fly everywhere and took quite a few tries to not hit a fizzler. thanks for creating another....
There is at least 1 exposed no-draw texture and a few visual quirks that should be fixed. For instance, why don't you have a hole and an arm under the flip-up panel that come out of the floor? Right now it's just a piece of floor coming out of nothing - it looks bad and makes no sense. I can tell that you put a lot of effort into the map's visuals but then things like this display a lack of polish and care.