Other mistake: When Ellen's brother leaves the bathroom as she's taking a shower, she opens the shower curtain to check that he has left. At the point she opens the curtain, you can see the top of the bathing suit she was wearing in the shower.
Other mistake: Marian asks Winthrop to go pick up a book called "The Indiana State Educational Journal 1901-1910". When we see her reading the book, it actually says "The Indiana State Educational Journal 1890-1910". (01:08:25 - 01:13:50)
Other mistake: During S Club's short press conference in Barcelona, the name labels on the table are not in the right positions. (00:04:30)