Dwight and Clark are rolling Stanley in the wrong direction. Since they took the stairs they would have come out the front door, yet they are rolling from the other end of the parking lot.
At 4:30, when Pam is talking to Nellie, Nellie's hair is in front of her shoulders. When the camera switches to Pam, Nellie's hair is swept behind her shoulders with none draped in the front. When the camera switches back, Nellie's hair is again draping in front of her shoulders.
The tranquilizer gun Dwight uses to shoot Stanley for the first dart is a single shot dart gun, however when he continues walking toward Dwight he immediately shoots him with two more darts.
He is then seen holstering a different gun which may have been done to imply he had a second multi-shot dart gun.
He is then seen holstering a different gun which may have been done to imply he had a second multi-shot dart gun.