[sosa]

You would either have to buy a new copy of CSS on Steam, or donate $15 to wL to get the current one unbanned. Don't take my word for it though, wait until either Bison, Riser, or Hamaerox respond to this confirming what I just said.

Donating $15 to wL would be preferable since the money goes towards maintaining the servers and you get to play on your main account.