Grimrock

I've been unable to survive getting the icefall hammer. At this point, I have very little tar beads for heals, nor have I been able to get to the exit. How did anyone survive?

Don't stand there and get beaten upon! Grab that hammer and run, then fight the critters at the entrance door.

Where's the exit, though? Only way in that area is to jump down. I've yet to find an exit.

Didn't you get what i wrote? Before you find the Icefall Hammer you open and enter a door. So run back to that door after grabbing the hammer and fight the critters there one at a time.

Clear out the basement first (by falling in other pits first), clear all the slimes, find the exit and be ready. From the icefall area the gate will be able to open to get out, not to worry.