with instructions on how to install mods for Heroes 5 and Heroes 5: Hammers of Fate.

If I'm not mistaken, mods for the Hammers of Fate are installed in the data folder, not in UserMODs, and they have the .pak extension. Be careful when installing mods; make sure they are for the correct version of the game. Most mods for the Tribes of the East will not work properly, or may not work at all, in the Hammers of Fate. The same applies to maps.