Can't find a specific cause. All I know that twice I crashed while quick loading at sea.
Once during the conversation with Captain Furrante, and second time while I was on the ship after the scripted interaction with the gods, that happens after I started sailing toward Neketaka for the first time.
Those crushes also don't seem to be creating dumps!
And I'm having difficulties capturing the error massage since I can't see it clearly until all dies. I think it's a runtime crash though.