There’s an issue with the resolution.

Tried it – didn't help, here's a screenshot.

Look for the file user_a2.cfg and the parameter setvar gfx_resolution in it. Usually, for Windows 7 and later, it is located in the folder: c:\Users[B]USERNAME[/B]\Documents\My Games\Heroes of Might and Magic V — Tribes of the East\Profiles[B]MAINNAME[/B][br][/br]
If it says setvar gfx_resolution = 1920x1080 there, change it to 640x480 and launch the game. See if the resolution in the game changes!