Other mistake: In the episode 'Anne' Kenn tells Buffy that time in his hell dimension passes more quickly, that one day on Earth is the same as 100 years in his dimension. This means time goes roughly 36,000 times quicker. When Lily falls into the portal, it's at least 10 seconds until Buffy jumps in after her, but Lily is still just sitting there looking stunned. If times moves that much faster, 10 seconds would become over 4 days. Would Lily still have been just sitting there?
Revealing mistake: When Buffy saves the man from being hit by a car, there is a very quick shot of the man standing in front of the car. In this shot, Buffy can seen on the left hand side of the screen running into the street to save him. But the shot then immediately cuts to Buffy who is suddenly still standing on the other side of the street with Lily and runs into the street to save him again.
Continuity mistake: In the episode 'Anne' when the latest people to be brought into hell are lined up with a demon talking to them, there are 3 or 4 people standing between Buffy and Lily. When the demon asks them all in turn 'Who are you?' we see him asking Lily and after that the shot rests on Buffy, but in the background we only hear him ask one more person before he gets to Buffy.
Visible crew/equipment: Near the end after freeing the prisoners, Buffy fends off Ken's henchmen on a raised platform. At some point during the fight she is grabbed by one of the henchmen and punched in the stomach by two others. She then breaks free and throws one of them off the raised platform - onto a large crash mat. Please note that this is a separate mistake to the one already submitted as it is talking about a different crash mat.