DEI Multiplayer not workiing for me

[Maize2]

Hello
I am relatively new to DEI and I subscribed to all 3 parts on Steam. From 1 to 3 ,in that order. I can play the campaign and custom battle no problem but when i go into multiplayer battles, it says that i have different version of the game therefore i can't play. Another thing to point out is that my infantry units are of 150 men but i see in other players is 200. Does it have to do the version of the game?
what's the solution to this? I tried unsubscribing and then subscribing again all 3 parts.

[KAM 2150]

Other players also need to have exact same mods in exact same load order for MP to work, otherwise you get different version message.
Your unit size can be increased in graphic option, change it to Ultra.