Just as Cardinal Campeggio approaches, Pope Paul III's chair is pushed in two times, and the servant departs in different directions.
Scene involving a sniper using a spring-loaded flintlock rifle, which wasn't available until the mid 17th century in England (over a hundred years from the point in the scene). The whole concept of sniping requires a reasonably accurate shot, which the muskets of the 16th century were not (i.e. needed the firer to prime the pan and light it, making fine aim an impossibility).
The episode covers the wedding of Henry and Anne Boleyn and her coronation in 1533. An aerial view of the current St. Peter's Basilica in Rome is shown during the episode, but the design for the current design for the building by Michelangelo did not begin until 1547. The dome was completed in 1590, and the final structure as seen wasn't completed until 1626. It is an interesting anachronism since a major part of the Protestant Reformation was fueled by the Roman Catholic Church's selling of indulgences in order to build St. Peter's, but it had not actually been built yet during this stage of the English Reformation.
Pope Paul III (Alessandro Farnese) speaks of the Jesuits (Society of Jesus), an order founded by the Basque Spaniard Ignatius de Loyola, but this was not done until Saturday the 15 August 1534 (O.S.) at Montmartre in Paris by him and his six companions, then not officially recognised by Paul III until Monday, 27 September 1540 (O.S.). Yet this is clearly set within 1533, as the Princess Elizabeth had not yet been born at the time of that scene, with Ann Boleyn still pregnant at the time - she was not delivered until Sunday the Seventh of September, 1533.
There is a citywide fireworks display that Lady Ann and her sister are watching. Fireworks were not used in large displays until the reign of Queen Elizabeth, about a hundred years later.