It depends upon what format your mod is in, what files it overwrites, and which it adds to. I guess you made it using the evo files - else activating your mod after Evo would mean that you remove files like universe.ini, market_ships.ini, market_commodities.ini, market_misc.ini, systems_shortest_path.ini, shortest_legal_path.ini, shortest_illegal_path.ini, mbases.ini - and those are the ones just off the top of my head.

I would try getting your UK based players to follow your exact instructions that make it so yours work. I get emails about how things don't work, and its because people don't follow instructions to the letter usually

The players in the UK all installed it as I instucted, same as US players. One weird thing, US players still saw it as Armageddon addon Patch v1_0_4
But the UK players seen it as v1_0_5
And thos are the ones that won't wrok, I sent them another copy, and still to no avail.
The mod is activated after evo, and it was just a mod that added a pvp system, but I expaned on it to add 3 new systems. with some bases , and wreaks.

Funny how US players see it, does anyone know if there is a differance in the UK version?
I would like to get it to work, please any imput will be helpful
Oh, btw , I am a NooB to modding, thats why I choose Freelancer explorer, and read the tutorial, keep this in mind when giving me info