I assume you mean BMTmicro?:
Was this the order form you used:https://secure.bmtmicro.com/servlets/Or ... D=73600003
If so you should of gotten an email and you download the game from the links they gave in that.
Also keep that email (save in on your computer if need be) - as to update the game you redownload it from that email.
If you mean something else though by xbt I am not sure what you mean..