At some point in the game, you'll need the elevator lever to activate the elevator, and if you are having a bit of trouble finding the Elevator lever is Ravenlok, then this short guide will to you where to find it and what to do with it after you've got it.
You'll be able to find the elevator lever in the Labyrinth of Mirrors which you can get to after completing the Dragon's Bribe quest and after defeating Shani the Sorceress.
If you are having trouble defeating Shani the Sorceress then basically to defeat her you need to break two rocks on the ground, then quickly attacking her with your sword. Don't bother trying to attack her while she is in the air, instead avoid her shots and focus your efforts on her friends.
So, assuming all that is ok, and that you can get access to the Labyrinth of Mirrors, you simply have to speak with the Crane , then keep going along the path until you find some items on a table behind Alina, there you will find the elevator lever.
How you have the elevator handle, use the mirror that is closeby to travel back to the Theatre Storage Room. When you arrice turn to the right and head up the hallway until you get to the elevator, you can use the lever there.