I travelled through the seaworthy portal, and on the other side I happened to find a touchstone, and then die. I was resurrected by the RoG touchstone without a problem. Then I died a second time.
I did not get the final death screen and it looked like the game was trying to resurrect me at the touchstone I had back in the SW world, but couldn't and it crashed, with a Windows message "don'tstarve_steam.exe has stopped working". The save still exists, but whenever I try to open it, it crashes as well, same message.
Activate touchstone in SW world, die in RoG world.