Overgrowth
Hey,
This is a test chamber I'm working on for the Summer Mapping Initiative. I'll be updating it up until the contest deadline; if people want to give me feedback on it, try to break it, etc. I'd appreciate it! 
Also, if you know how to use the record demo console command in Portal 2 and want to send me the demo of your playthrough, that would be extra-useful as I want to see how people approach solving stuff.
Changelog:
v0.1 - first version of map
v0.2 - made stairway on third level more noticeable, added convenience for returning to lower levels from the end if cube needs to be repositioned, added foliage, made water at base of testchamber transparent, various minor graphical tweaks, added glados line
v0.3 - fixed portal alignment issue at top of chamber, fixed brushes that could have interfered with box dropper entities, lowered box dropper and made box target into convex displacement map to reduce the likelihood of it bouncing away
v0.4 - put invis collision around top of drop from upper light bridge panel & adjusted platform spacing to prevent a way to break the puzzle; made final light bridge panel hidden until the player presses a button on the upper balcony, changed voices and music trigger timing, added another convenience portalable surface and closed off an unnecessary stairway to vary movement/pacing, various visual changes w/ ruined structures, foliage, fog settings and pfx
v0.5 - made some more gameplay alterations to make movement through the chamber more interesting, improved lighting, updated vo, sound, and transition entities, did some optimization, added more func_details and props, pfx, etc.
File Name: Overgrowth.rar
File Size: 4.92 MiB
Click here to download Overgrowth - MAJOR UPDATE
Nice map. The scenery is awesome. I think you need cubemaps, however, because a lot of your objects like
Good puzzle and nice decoration. I'd look in to adding a few more sound scapes and music changes as you make your way up the level so that the loop doesn't start to bother.
Whooops, i broke it on my first, blind ride. This can't be the intended solution:
http://infernet89.altervista.org/down.p ... rnet89.dem
I'll retry now for finding the correct way.
EDIT: ok, solved in the correct way. Maybe you can
(I'll stop recording if i die.)
Impressive on both visual and aural fronts, with peaceful vistas and reflexive music not unlike looking from the bottom of a tomb raider level. More about exploration than puzzles, which become a bit basic once you see the way to get to the top.
I didn't find any use for the lower gel pipe. All good, the only detail I didn't like were the plain looks of the stone stairs. Here's the demo (it's the way I followed, just faster than the 1st time):
http://www.mediafire.com/?iiqvr29urg84p6j
Looking at at infernet89's suggestion, I believe I've found the same quick-solve route. An emancipation grill that limits access to the different levels perhaps?
I recorded a demo. I don't think I did it right :S Nice looking map though, stairs were a bit much and that long hallway that the bridge goes through the fizzler.
Thanks for the feedback and demos everyone! I made a lot of updates to the level based on what people said. Some specific things:
-made some changes that have probably fixed a bug with players being able to bypass the first part of the puzzle (combination of invis. collision, shifting of ledges, removal of unnecessary platforms and having one explicitly triggered later on)
-blocked one of the stairways with ruins and set up another portalable surface to speed up the early part of the map
-put env_cubemaps around, updated a lot of visual elements
Please keep testing this map and let me know what you think / if you can break it, etc. The demos have been really useful for understanding how players see the level, so please keep sending them! 
A really nice map, I love the sweeping vista when you walk into the chamber and look up, this could win on the visual front just for the view of the sky.
Nice map, yet the game not ending was a bit confusing at first, and "End of Playtest" Default endgame text was a bit odd. (msleeper has nice modified transition ent you could use). Otherwise, i did like the gameplay, and the level design.