Continuity mistake: In the scene where Astrid tells John at the airport that Stuart is dead he cries and hugs her. In reality he began to burst into laughter . Astrid herself said: "He never cried. Not once. He went into this hysterical laughter and couldn't stop. It was his way of not wanting to face the truth." (Lennon- The Definitive Biography, by Ray Coleman).
Continuity mistake: Near the end Stuart opens a package containing the Beatles' first single. When it shows a close up of the record you see a cigarette in his right hand, but when it cuts back to the shot of Stuart he doesn't have a cigarette.