Looking at the Netherlands on the campaign map, I noticed some inaccuracies:
- Utrecht, Groningen and Friesland are named duchies, but are lordships. (The Lordship Groningen being renamed 'Stad en Lande' after it joined the Union of Utrecht, this of course only recognised by the Dutch themselves).
- Drenthe is not a county, but a lordship.
- Zeeland is gigantic, including the south of Holland (Rotterdam, Dordrecht), Brabant (Bergen, Breda, Tilburg) and Flanders (Gent, Terneuzen).
- There is a minor city north of Amsterdam called 'Helder'. The current city of Den Helder, further to the north, didn't become an important port until late 18th c. A better name would be Alkmaar.
Also, in 1618 Breda was controlled by the Republic, and Gent by the Spanish. And in 1618 there was still a truce with Spain (until 1621), though I suppose war at the start is needed for gameplay reasons.