By chance did you have any crashes during or shortly after a save? I remember hearing of a few similar incidents over the years when people had a crash during a quick save (on both the classic and EE versions) and it caused fog of war or area-states to seriously glitch out.

Has this been occurring for your entire playthrough or did it only start happening at a specific point?

Is this only happening in certain areas, or is every map resetting when you leave it?

Is it only happening in this game, or does the problem also occur if you start a new game?

Are you using any mods? If so -- and the problem keeps happening in every new game -- try doing a clean install without any mods and see if the problem still happens then.



As far as fixing your current save... I'm not sure if this would work, but you could try opening your saved game in EE Keeper (https://sourceforge.net/projects/eekeeper/), make a very small change (give yourself 1 gold piece -- just so something about the file has changed) then re-save it from EE Keeper. Again, not sure if that would actually do anything. But it's possible that if some of the save data is in an invalid state that EE Keeper will try to put it back into a semi-workable state. Of course, it could also muck things up even more -- so backup your save first.

Fortunately, if you do need to re-start, Nashkel isn't that far into the game, unless you did a LOT of side questing on the way there.