Continuity mistake: Frasier and Roz are in the kitchen talking, and Frasier says "over thinking things can spoil anything", and we can see Roz lifting a glass of water in her left hand. The shot changes and she now has her right hand up to her mouth and a split second later there is a sticky bun in that hand.
Continuity mistake: Roz is talking about having a fling - while she takes the notebook, which was open on the coffee table, shuts it under its own weight. She keeps talking and waving her hands around, and in the next shot the notebook is open again, even though she didn't touch it.
Continuity mistake: Toward the end of the episode, Frasier and Caitlin are talking at her apartment about their status and she is sitting on the side of his chair. He has his right hand between her knees and left fingers tapping on her left thigh when he says, "well, I have been terribly worried about this global warming situation." Immediately in the next shot when she responds to him, she is holding his left hand with hers, and his right hand is down on the chair.