Deliberate mistake: When Ringo sprays his assassin with orange juice, it doesn't reach as far as the sofa. But it still splashes over the inch-high Paul. Even if it had flown that far, Paul is on the far side of the sofa and the angle is impossible.
Deliberate mistake: The theatre is said to have been closed down "years ago". But all the theater props are still there, and the place shows no sign of disuse, it is not even dusty anywhere. The electricity and water are also still hooked up and functioning.