nosferatu warrens 4

[s.weasel]

After I killed all the creatures stalking the tunnels I saw a big computer , but the control case was locked and I couldnt open it.
In the walkthrough it says that I should see a nosferatu battling two of those creatures but I didnt see anything like that.
By the way, I went into the warrens just after I killed the tzcihimizte ( or however you spell it ) Did I have to go to somebody and get this quest? I remember Isaak telling me to directly enter the tunnels though ....
Any ideas?
Should I start from the beginning of warrens 4 ?

[the_limey]

The keycard you want is further back on level 4- from the control room go back to the incline that leads upwards, then take a left and follow the wall around, keep going in the only direction you can until you reach another incline- the nosferatu you're looking for is somewhere around here, but he doesn't have the card it's on a corpse nearby.
Sorry if it's a little off but it's been ages since I played.,