Yes, when I click "create map" in the game and choose the parameters for it, as well as downloaded maps: they open in the map editor, but when I launch the game, they are not visible.
And how exactly do you have NCF installed?!
Based on the symptoms... either NCF is installed incorrectly, or you are launching the wrong NCF-compatible .exe file.

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Неудачное планирование ведёт к неудаче ...
NCF - мод, добавляющий дополнительных существ в HeroesV 3.1