Overall, this was a great map that I gave a 5. The last chamber was definitely stronger and more natural than the first. I liked the first, too, but the challenge, both mentally and physically, of the last was terrific. And I loved the
fake exit. I had a feeling something was up when I saw the button w/ only a light bridge between me and death, but that there was a whole other chamber behind the alternate route was a really big payoff!
I think another sign you've got a winner here is people comparing notes in thread about how the solved the final chamber. Seems like everybody took a different route...including me. Here's what I did:
1. Hit the push button. Let the reflecto cube fall, portaled the target wall and the right-hand wall, stepped part way through, grabbed the companion cube as it fell.
2. Engaged funnel w/ comp. cube.
3. {tried some things that didn't work}
4. Portaled the top panel and the left-side panel so funnel was coming back toward me from the ref. cube side.
5. Hit the push button. Ref. Cube dropped into the funnel, headed toward me.
6. Ran backward toward target wall.
7. Portaled left-side pillar floor when ref. cube was over it. Ref. cube now going vertical.
8. Quickly moved other portal (the one accepting the funnel) to the right-side panel.
9. Allowed ref. cube to fall through first portal to fling out of second and onto the right-side button.
10. As soon as ref. cube fell through first portal, moved first portal to target wall, and collected comp. cube as it was falling, just as in step 1.
11. Put comp. cube on floor button to active funnel again.
Final note -- in the first chamber, I was able to fling the monster cube through the grating on the wall where the funnels come out of. I could not walk through the grate, though.