Requiem: Help I'm stuck not sure which level

[Keth]

there dude, I've done it

Spoiler below!

You must go back to the pistons room and at the last piston (the piston near the room with the first handle) is a small vent on the left of the piston room, there is a laser beam that deactivates the lasers above.

Hope I've been helpfull

You mean this vent and those pistons?

Spoiler below!

I don't see any laser beam there or any switch to deactivate lasers.