In the first battle single shot flintlock pistols and muskets are fired multiple times without being reloaded.
At the very beginning, in an office at Royal Navy Headquarters, there is a Union Jack in the background. It's the modern flag, with a St. Patrick's cross (the red X over the white X of the St. Andrew's cross). This flag was not adopted until 1801. The flag in use in Blackbeard's day did not have the St. Patrick's cross.