HoMM3 HD is a mod (add-on) for the game Heroes of Might and Magic 3.

"Now, the template is selected from some unknown source," which doesn't quite align with the fact that you know about the "HiRezData folder and its Templates subfolder." Everything is conveniently selected and saved. For myself, I left only the templates I use in the folder – and the list is now smaller. Before, I had to manually change the text file every time, and only one file at that. I don't see a problem, and I don't understand what the "nonsense" is about.