I am stuck in the part of the crypt after you meet Scabban. There is a room with a pool in it that has a grate in the middle of the pool, but it's closed. I can't seem to find a way to open it (or any other way out). Any help greatly appreciated. I found a button on a wall in a nearby room but it didn't do anything. Thanks.

go back to the room where u meet Scabban first... there is something to push