AfricanWishbone: So I was looking through game files and noticed references to a green nation. I managed to add them to mission 01 and they are a Portuguese faction! Looks like they haven't been finished and shipped with the game files. The voiceover/announcer even says 'Portuguese port sighted' when you come across it.
They even seem to have a Corsair too. Managed to attack a Port I added and everything worked as expected.=
I wonder if it is possible to make them playable. If not, I'll update my Adventure Mode mission files and add them in!
Added a screenshot of a Portuguese port in mission 01.

AfricanWishbone: I have managed to assign them a port by updating mission files, just assign a port to green. This doesn’t, however, mean they behave as a regular faction. I haven’t assigned ships to them yet, and they are unfinished so will need to assign ship names etc…
Currently looking if it’s possible to add adventure mode back into the game so I don’t need to mess around with updating mission orders to play them, then If successful I’ll either make more maps for adventure mode, or add additional playable factions to each mission, then I’ll add in Portugal to each adventure mode map.
If this all works I’ll add instructions to update your game / updated game files.

punkamisto: That seems a lot of work and I still have no idea how to do that.Thanks a lot for trying , really hope it´s possible. I ´m sure my father that played the old game so much would love to be able play it again 20 years later and with its home nation :D
Again, thank you for your hard work and hope it all goes well.

AfricanWishbone: I have made a new thread in the forum to track my modding progress, have worked out how to update the game, tedious and a lot of work but keen to give it a shot. I can't guarantee I can get Portugal to be playable though, as there are a number of files which I would need to manually add to the game / make myself.