I was leaving the Lonely Rock(that name might not be exactly correct) area by boat and chose The Blue Mushroom.
When I went below decks, the transition put me in a bedroom with a specific key door instead of in the hallway, but the area's still called "Dark Lake-Sailing-Below Decks"
I figure it'll be as easy as waiting for a DM to log in to teleport me out of here, but if the transition always does this, then it's a bug!
Was probably just a NWN quirk.