Continuity mistake: Rosalind goes to the bandstand to play the trumpet. The trumpet player is seen standing up, handing her the instrument. Cut to the same man also seen sitting & shrugging at the pianist. Cut back to him standing.
Continuity mistake: When Alan is first stopped by the motorcycle policeman there are three cars on the road behind him, as Alan pulls over none of them pass him, but a truck does that was not in the previous shot.
Continuity mistake: The day after the race Alan and Wendy are sitting at a table outside a pub - Alan's beer is on the table but when the angle changes when Ambrose sounds his horn, Alan's beer is now in his hand - it has changed colour and there is less of it in his glass.