Hi GeeGee, The room you are talking about is the revolving knife room. That was the only room that I couldn't get back to, because I went up the water elevator first. I went back to a saved game just to see if I missed anything. I didn't, and no way was I going to try that elevator again. I got lucky and made it once. You don't need anything in that room. You can get to all the other rooms.
Kay