Registration as Enfold Theme Purchaser

Hello. We have purchased Enfold with the 12 month optional support but cannot find anywhere how to register this purchase with Kriese.at. It is not even clear who Envato is and how it relates to ThemeForest, both of which appear, somehow, to be the seller. How do we make ourselves known to Kriesi as a legitimate Enfold theme purchaser? In particular, how do we log in with a UserID and Password at the Kreisi.at support site? We do not see an option for registering the purchase with Kriesi. Thank you.