Guys, we downloaded Heroes V.

3 Intel Core cores

My question was (and the answer is hidden within it) not about the number of cores, but about the size of the maps and the number of players – the difference is significant.

Added 6 minutes later
So, the question is about the maps. We found the standard maps in the data archive, extracted them, but when we try to select them through the editor, it says "It doesn't see suitable files" and it's the same in every folder... what's the problem?

The problem is in the editor mode – it can only open standard maps (those in the "data" folder) in extended mode. ;)
*** {In the "Profiles" folder of the installed game, open the "editor_a2.cfg" file and change the value of the line "setvar map editor mode = 1" from 1 to 0}.