For users wishing to purchases upgrades, the email address in our download database must match the email used when creating an account at the Sagan Technology store. Fortunately a new feature in the Sagan Technology Download Center shows the current email address of logged in users and allows them to change that email address.
So if you want to upgrade, first log in, verify that your email address shown there matches the one you used to create an account in the store and you should be all set.
If you have any questions please contact support via info_AT_sagantech.biz