I've killed the crypt keeper and found Marten's crypt key among other things. Is there any way to open the padlock. It says there is an item required. I suppose it's not really necessary since you can get around it, but I'm curious.

There is a 2nd key, I forget its name, that opens the wall to the shore from the crypt area. I think the cryptkeeper sometimes drops it. Sometimes I have got it from killing Marten after you get the doodad.

After you talk to Marten and get the doodad, he gives you the Sea Caves key as he departs. So go talk to Marten ;)

<center>Nightowl2</center>

You don't need it, though, there's many ways out of there; just fall down one of the many slippery slopes and leave from the cave below. Or Portal, if you're magical enough.