http://www.kiya1.de/beyond/actgeneral/crystalbag0.png

click on the bag - inventory openes - drag inventory next to your main inventory and then look on my screenie <img src="/ubbthreads/images/graemlins/winkwink.gif" alt="" />

The 4 talking levers (sequence: NW, SW, NE, SE) say a sentence => Beware of the traps => then the foor is open.
Kiya