Its because they use a Torrent system, maybe they used great part of your bandwith to send instead of receive, since the system noticed that you have a internet so good like that.
I've downloaded and installed the game.
Also what is TERA?
My nick is a surprise
Also I cant add Gunlord, I think he isnt playing in the US server maybe? Trying to add anyone here in the BR server doesnt work, so I created a account for the US server and added everyone.