Second day Macbook user here. I tried installing VCMI (latest build) and the the fullest Heroes 3 version without mods. I downloaded the essentials pack and if I choose any other error then 800x600 I get this message:
terminating with uncaught exception of type std::runtime_error: Requested screen resolution is not available
Other than that, the game seems to be working ok with default resolution. Where the problem can be?