A suggestion for checking a few things on level 1 before we take the elevator down:
Go north-ish & check the door to the east of room 16.
Then, proceed through room 18 & check the north wall of that room for secrets (there's a skeleton there pointing toward the north wall). Beware three skeletons that may be hostile there.
From room 18, round the corner through 19 to room 41, into which we will cast light.
Once we've wrapped up those possible mysteries, on to the elevator & downward!
[f=32]Wiglaff the Elf, F3/MU2
(M 12", AC 9, HD 4+1, hp 14/14, N) cloak of elvenkind
, battle-axe; light, colour spray
[f=47]Wilibald "Willie" Whitfoot, F1/T1
(M 12", AC 6, HD 1+2, hp 9/9, L) gambeson+helm, shield+warhammer[/f]