For multiplayer you will need to install several successive SP's to get your trainz-build up to TS 12 multiplayer/
He really does have TS12 installed and registered on Planet Auran ... I seen his N3V account with my very own eyes, via Skype view screens.
He needs his TS12 account refreshed, as well, by N3V, just like they refreshed his T:ANE CE account.