During the Trio's "James Bond" discussion, Jonathan claims that The Living Daylights (1987) was "written for Roger Moore". In fact, Moore had announced his retirement from the role of Bond long before work on The Living Daylights began - if written with anyone in mind, it was probably Pierce Brosnan (who had in fact agreed to play Bond in The Living Daylights, but was forced to withdraw due to his contract with TV show Remington Steele (1982) ). This could be regarded as an intentional error, but it's unlikely that such an apparent James Bond obsessive as Jonathan would make such a mistake.
When Andrew plays the pipe flute his mouth is nowhere near the notes that are emanating out of it.
When Buffy and Xander are walking through the construction site and Buffy is talking about time fast forwarding, you can see a crew member following them with a light diffuser. The goof is hardly noticeable, as he looks like a construction worker going about his business.
When Warren makes the world fast-forward around Buffy, we never find out how the rest of the world sees her. At one point when he activates it, she is face-to-face in a conversation with Tara. If Buffy suddenly disappeared or seemed to stop moving, why wouldn't Tara panic? Instead she just leaves, and Buffy follows her outside where super-speedy students knock her down and kick her, apparently unaware of her presence. Yet they're the ones moving too fast to see, not her. She, instead, should be like an indestructible "statue", perfectly visible by all.