HoMM3 HD is a mod (add-on) for the game Heroes of Might and Magic 3.

Is it possible to configure the system so that RC1 and RC2, and subsequently other versions, do not conflict with each other, and all options are available?

The thing is that the TournamentExtension is linked to the ability to play online with corrected game bugs. And in RC1 and RC2, towers deal different amounts of damage (see the beta changelog). This is precisely why RC1 and RC2 were made incompatible with each other. What about future versions? This depends on what changes will be made to them.