I'd suggest not using this mod in multiplayer, for exactly the resaons you describe. When the mod renames a city it's only applied to the local machine, so everyone will always end up with different names. A possible workaround (which I haven't tried, but should work in theory) might be to open up the City Details panel and manually change the name to something else, then back again. That will populate what you typed in to all players, but you'll have to remember to do that every time the mod renames one of your cities. The trouble is that there are actually two different Lua commands the game uses to change city names. The one that works over the network: CityManager.RequestCommand(), can only be accessed by UI code, so to do stuff in response to gameplay events I'm having to use pCity:SetName() instead, which only works on the local machine.