Joric is "good" but is being manipulated by the voice which is the sword and the earthquake is caused by the guy who built the keep who turned into something evil. Or that's my guess.

And the guy who built the keep is also possessing the sword?

EDIT: Also, Dasmira stashed her gold under a floorboard under the bed that had loose nails, so she removed the nails from a board across the room and replaced the nails holding the loose board with them, making sure they were really tight and perfectly angled. That way, the board looked exactly like all the other ones.