When the British land at Barataria Bay to confer with Lafitte, a rocky shoreline with short cliffs is shown in the background. But Louisiana is in the Mississippi delta which consists of mud deposited there by the Mississippi River over the Ages. So the land at Barataria Bay consist of mangroves and mud, and NOT rocky beaches or short cliffs on the shoreline.
Andrew Jackson appears as he looked at the time of his Presidency: 62 years old and white-haired, just as on the $20 bill. At the time of the Battle of New Orleans he was not yet 48 years old and his hair was still red.
When the British are conferring with Lafitte they offer to pay him $30,000 in gold. BUT the British would not have made such an offer in American dollars. Instead, they would have offered the reward in British pounds.