I had same issue during coop with my friend. He got the bug (he was joining my game, I was fine).
We did some testing. I believe that issue is related to spawn near friend option and randomly generated map:
Navezgame: Spawn near Friend = NO BUG;
Navezgame: Spawn in random location = NO BUG
Map from random generator: Spawn near Friend = BUGGED;
Map from random generator:Spawn in random location = NO BUG
Also spawn near friend worked differently on random generated map, my friend was 900m away, while on Navezgame it was maybe 50m
Also:
I installed game just before 2.0, I turned it only once to see that it is still 1.4, then I shut it down and switched to experimental few hours later.
Game had my old save still stored somewhere
My friend did full wipe, issue did not disappear.