While showing us "Danish" castles and buildings, the movie's opening sequence included a shot of a castle flying Czech flags (blue, red, & white). Like the first movie, parts of the sequel were shot in the Czech Republic.
When Paige at a press conference admits that the Danish language is her biggest challenge, king Edvard says - in Danish with a heavy British accent: "Du bli'r hurtigt flydende!" (= you'll get fluid quickly!) He meant 'fluent'. In Danish he might have said: "Du vil hurtigt komme til at tale sproget flydende."
The "loop hole" in the law states that the commoner has to have knowledge about the Danish constitution. This law is from 1282. However the law Paige is reading is from 1953. The earliest constitution is from 1849. However this can be a confusion with the Code of Jutland which is, as stated in the beginning of the movie, from 1241 (but never considered the Constitution of Denmark).
At numerous times throughout the movie, Paige is referred to as "Crown Queen Paige". This is incorrect. She should have been called "Crown Princess Paige", since she is a princess. There is no such title as "Crown Queen".
Also, the correct salutation is: "Her/Your Royal Highness, Crown Princess Paige", or, "Her/Your Royal Highness, The Crown Princess". The former form, however, is accepted in public, when members of the Royal Family are not present.
In the first Prince & Me, King Haarald is sick and dying, and that is why Edvard leaves Wisconsin to return home and become king. In this movie, Haarald appears to be alive and well. Also while walking through the garden with the busts of former kings, on looks a lot like James Fox, who played the character in the first movie.
The goof item below may give away important plot points.
When she presents him with the ancient big book, he looks at the opening pages and sees the answer to their problem. But when he uses it in the Church, he opens to a page closer to the middle of the book.