Go to C:\Users\[USERNAME]\AppData\Roaming\Tailbound. Does the file labelled permanentOLD.ini exist? If not, that means your permanent.ini file from the previous builds is missing. If it IS there, then I'm really not sure what went wrong, unless you somehow cleared the file and regenerated it when re-opening the game.
The new area isn't visible on the map, but it's connected to this room: