Welcome to the forum. What's Gameranger? Never heard of it. If you have the game you should be able to find other players depending on whether you have a Steam or GOG copy through their multiplayer connections.
I thought Gameranger or program with similar name was used in past as some kind of client for online multiplayer games?
It's usually used for games that no longer support multiplayer officially, used it several times for Battle for Middle Earth 2. But yeah, Medea's right. If OP has TQ:AE they should just be able to play multiplayer normally without any third-party programs (I don't use GOG so I don't really know about it and it's multiplayer functionality but I would guess it's the same way)
P.S. Welcome to the forums!