The prince's shirt goes from unbuttoned to buttoned during his first meeting with Beau Brummell.
The final meeting between a dying Brummell and George IV is fiction, as the King declined the meeting and Brummell was not on his deathbed at the time. He outlived George IV by ten years.
Brummell never protested against the Prince in public speeches. This is pure dramatic invention.
When the mad King George III hides from Brummel and the prince behind the draperies, the boom shadow makes a prominent appearance on the wall at the top right of the screen.