First, the pop-up normally appears ONLY when the activation server cannot be reached. Since both Esellerate (until Sept 30th) AND Soraco ( the new server ) are online now, the only possible reason for seeing the License Wizard, is because you have a firewall that is blocking access to BOTH servers.
So, first try to fix your firewall/antivirus problem, because this way the activation will be much easier.
However, the offline activation would work as well, but if you bought the product before July 1st, you need your new Soraco activation key, because old Esellerate keys cannot be recognized by the OFFLINE License Wizard, so you need to know the new key that has been associated with your old Esellerate key.
There's no reason why the email sent to you by Soraco is blank. I tried it now, and the email is surely readable, so it must be something in your email program. Try reading the email with another program or using webmail.