I took me ages to find that corridor. I think I was blind for a while, lol
I am sure the switches are in the areas past that long, narrow corridor. Ome of them is in a room with lots of small pools.
I am sorry I can't be more specific but I got utterly lost. Mazes seem to be beating me to bits, lol
Good luck

My dwellings: The Glade and Eridani'sAnyway, if I wanted a complex story led by dynamic characters that aren't easily categorised into facile dichotomies of good and bad with no clear arc or easily predicted outcome, I'd have left the theatre and lived my damn life. Brownian