In the long shot in the village of 'Bletcham' the notice board has writing above it, presumably including the village's real name. Closer up, the writing is missing.
During the car chase in the countryside, the rounds of ammunition being fired at Frank Haleton, are ejected from the rifle backwards, with the bullets still intact.
When Diego starts firing at Halleton's car, some bullet holes are seen forming on the side. The holes are round, which would only happen if the bullets came in from the side, but all three guns firing are at the back of the car.