Joining the lobby should be possible from anywhere, unless your country blocks it. Joining someone's match on the other end is another matter. The only solution would be dedicated servers you can join, and that requires money.

It should though... Mods should install next to public if thats passed.

P.S. I am aware of the option ' pyrogenesis.exe -writableRoot"     to store runtime game data in root data directory, but this is not it in full.  

It does work, but indeed, a more flexible way of installing everything into the same directory (including mods, logs, maps, etc.) would be nice, so that one can have various independent versions if desired.

It’s probably an issue with a public IP or port settings. I really hope that in the future the game will be released on Steam with proper, fully functional multiplayer for everyone, because after a year and a half my friends and I came back to 0 A.D. and once again found ourselves trying to figure out how to join the lobby — using VPNs, Radmin, and other tools just to play normally, which doesn’t really help.