All questions regarding mapmaking for Heroes of Might and Magic 3: The Shadow of Death.

Vovalium, to ensure that the lands are hidden in darkness at the beginning of the game, no action is required. Only the territory around your castles, heroes, mines, and dwellings is displayed. The entire map is revealed only by the Grail in the Tower (Sky Ship). So, you may have misunderstood something. Another option: perhaps all the players on your maps are your allies? Then their territory is also displayed immediately. What kind of maps do you have? Can you attach at least one to the message?