PoA Computer Game- NEED HELP!!!

[Tamara]

I am playing the HP PoA computer game and am completely stuck on one 
part. It is where Harry and Hermione are in the tunnels to save Ron. 
They are in a large room with two sets of stone steps. I have defeated 
the skeletons, and opened the two chests, but I can't figure out how to 
get out of the room!! I've moved the stone steps around a few times, 
but nothing works. Anyone know what to do? And explain it to me like 
I'm stupid please. Because that is how I am feeling right now lol. 
Thanks!

Tamara