Enter the dungeon from the SW corner of the outdoor
part of the Spine.  Kill a few lizards, and follow the
passage to the west.  Pass the intersection and enter
a rectangular N-S chamber.  Walk through the middle
of the chamber, and exit the room at the north end to
the east.  The first intersection you reach, head
north.  Continue north at the next intersection.
Stop in the small 2x2 chamber at location (19,27).

Use the runed stone you got from the thief at the
inn.  The other does nothing.  You should get a
message about a green glow, and see green runes all
around you.  The trail of runes needs to be followed
_exactly_.  If you wander off the path too far, 
return to (19,27) and try again.

Leave this chamber down the path to the east/southeast.
At the first intersection, head NE.  At the next
intersection (a "T"), follow the runes to the east.
The path should lead to a large room.  Go anywhere
inside the room, but don't wander down the side
passages.

In this room, depending on how far you are in the
scenario, you will fight some drakes.  If you've 
gotten past the tower, Gwennyth will join your party.
If you haven't, she'll give some advice and leave.  If
you haven't been to the tower yet, she won't appear at
all.

Once you've killed the drakes, follow the runes to the
northeast again.  You should reach another "T" junction
with three runes next to one another on the wall.  Walk
through the middle one at (48, 18).  Follow the secret
passage until you leave this area and enter the next.