If you finish the Quest and leave the Building through the gate, do NOT re-enter the building. Because the side door you have to pry open in order to enter the building will stop working. Not locked, but literally stop working and trapping you inside, softlocking your progress.

You also can't reach the hall again, where you leave the building upon quest completion, because the door connecting the staircase with the repair hall will also stop working.

There is a floor gate in the repair hall, but it requires Tech-Level 10 and I have only 9, so i can't check if it leads anywhere.
My guess is that it's just another alternate path through the hazardous environment.

If you got stuck like me inside the building, like myself, than you have to reload a previous save file.


PS: The minimap won't show any "breadcrumbs", meaning that even the game doesn't know how to leave the building.


Merry Christmas