This is where the game gets kind of crazy and confusing. I know that, to this day, it still bothers me in a small way that there was a lock I was never able to find the key for.
Teleporters: Did you know that some of them are invisible? The same goes for those plates on the floor. And I think you are at the point where almost everything regenerates.
One of the ways I was handling teleporters was to either set something I didn't really care if I lost, a stone perhaps, in the teleporter to see where it ended up. I figured this out after I cast a fireball into a blue teleporter only to have it come up from behind me and almost kill my entire party. Great idea!
Three games I have shrieked out loud while playing. Dungeon Master, Bioshock and Dead Space. And I don't scare easily. Ask my mirror.