While it is true that the monument of Frederic Wilhelm was made in a new casting house, the house was agreed in 1696, not in 1700, as suggested in the movie.
It is historically not secured if Andreas Schlüter ever worked in Dresden, as show in the movie.
In the movie King Frederic I is ordering Andreas Schlüter to build a huge coin tower after the work at Castle Lützenburg (later Castle Charlottenburg). In real life the works on the tower began in 1702, before the other projects were finished.
When showing the plans for Lützenburg Castle Baron von Eosander suggested to Sophie Charlotte von Hannover to rename it in "Charlottenburg". In real life it wasn't meant like this. The castle was renamed only after Charlotte's death in 1705 in honor of her memory. In the movie however the castle is referenced as "Castle Charlottenburg" even while Charlotte was still alive.
In a scene set in 1697 Elector Frederic III mentioned that the duke of Hannover gained the crown of England. The House of Hannover didn't gain the British Royalty until 1714 and didn't gained a chance to get it until 1701.