A tarmac road can be seen on the left when Moonraker is chasing the soldier across the country.
Stonehenge is shown with a path around the stones but it all only became an organised tourist attraction in the early 20th century. Up to then the stones would have been set in just grass.
The Roundhead troops wear red sashes. This was the sash colour worn by Royalists - Roundheads wore tawny or blue.
Prior to a fight with Gregg, a sword is pushed into the Moonrakers chest, and it bends without causing any damage. In the actual fight, this same non piercing point slashes through shirt and skin leaving a lot of damage.
Several proclamations are seen in which Oliver Cromwell is described as "Lord Protector". The film in set in 1651; Cromwell did not adopt that title until 1653.
When The Moonraker is walking in the village (actually Lacock in Wiltshire), there are a number of modern doors on the houses to his right containing door numbers and letterboxes, neither of which existed in 1651.
Both Lord Dawlish and the Roundheads are seen riding over a grass verge adjacent to a modern tarmacadam road, which would not have existed in 1651.