Well, I initially thought the same, but these videos...
Especially the ones about Excalibur and Dungeon & Dragons – they are very well made. Professional translation. Disc from Far Gus. It seems that Buka simply didn't have time or didn't want to localize it.

Read carefully: Heroes 4 and its 2 expansions, "The Coming Storm" and "Whirlwinds of War".

Developer: New World Computing
Publisher: The 3DO Company
Publisher in Russia: Buka Entertainment

However, New World Computing and The 3DO Company have long ceased to exist. All rights to the game belong to them!

In Russia, only Buka has the rights to publish Heroes 4! Therefore, no other company can release licensed discs with any expansions for Heroes 4. I myself have seen discs with Excalibur, Dungeon & Dragons, Alexander, and Lord of the Rings from the company Far Gus. But, as I repeat, these are unofficial releases. Which, in no way, can be licensed. Maybe I'm wrong, but the license is held only by the company that has the rights to publish such games! So, these are just amateur collections of companies and maps. Perhaps they are indeed well made... (I myself played the campaign for the Dragonling once). But no one guarantees their functionality and possible bugs :smile38:

So, if you really want to play properly, buy a license from Buka. So that you don't have a bitter disappointment later that the game is almost finished, but some glitch prevents you from completing the mission.

More precisely, you can play on anything you like at home for your own pleasure :) But if you want to play online, you will have to buy the original game and expansions. Because there may be failures on the pirated version. If you can even play with anyone over the network.

And also, it's spelled "Equilibris" :) And not "Equilibrium" ;)
And as the respected Lars already said here, it may not work on pirated discs. Or you installed it incorrectly.
Well, and carefully read the post by Dr Motor, maybe something from it will help you :)
And in general, it is best to install both expansions on the original game, and then only Equilibris :) Don't forget about the files heroes4_sfx.exe and camp_ed_sfx.exe :) Everything should work.

And enjoy the game ;)