To install unzip file and place map files into your folder named
Steam\SteamApps\username\portal\portal\maps
to play the map, run portal, go to bonus maps and click on chamber23. is this dose not work for some reason, open the dThe underlying concept of this map is the use of physics objects with portals. This map is playable all the puzzles work 98% of the time (do to the conflicts between portals and the physics engine).
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