Withholding my rating for now, but I also hit the same bug Victrio did, below.
To be more specific: returning to the foyer after fighting the lab technician zombie, I found the lady STARS member missing, with some ammo on the ground. I went to the second door from the left (against the back wall, not the one appearing to lead left) and hit enter. A message appeared, but I didn't get time to read it (I must have pressed the enter button too quickly?) and I traveled to a dark room with an ineffectual flashlight. I went to the other end of the room and turned on the light, then fought the zombie(s) that were there. The door leading right needed an emblem to open, but traveling left did not bring me back to the foyer again. I was trapped.
I also didn't appear to be able to open my inventory, and hitting enter did nothing anywhere in the room, after hitting the lightswitch and testing the door.
An interesting game, but I don't think I got nearly far enough into it to give a proper rating.