Continuity mistake: The butler and Frasier are discussing the new president of the opera board and Ferguson pours Marty a cup of coffee. In the next shot, over Marty's shoulder, we see he already has the cup in his hand, although there was no time for this to happen naturally.
Continuity mistake: Roz is at Frasier's soirée joking with Mr. Worth about selling him some giftwrap. Just before she says "everything but my bracelets", her drink and hat switch from her right hand to her left and her canapé from her left to her right. In the next shot they've switched back again.
Continuity mistake: As Catherine is about to leave Frasier's apartment near the end of the episode, you can see the white shirt she is wearing constantly changes between shots. At times it is hanging out very loosely and in other shots it is neatly tucked in and positioned to the right.Lummie
Plot hole: Once the gang have arrived in Canada, Daphne is scared stiff of getting caught outside the USA. Marty explains they will just "smuggle" her back and Frasier and Niles are outraged at such deception. But to get into Canada, all of them would have had to declare their residence, birthplace, and reason for coming in. To get Daphne in in the first place, they must have lied. She would have had to show her passport as an alien. The Americans would have been allowed in without their passports, per diplomatic agreements. So the outrage of the boys makes no sense.
Continuity mistake: In the restaurant, Frasier and Ann are at Kenny's table - Kenny puts his napkin down and leaves the table, while Frasier puts his cellphone away. In the next shot, the napkin has changed position on the table and Frasier is putting his cellphone away again.