I couldn't find a way either. When adding the upgrade to shopping cart the key sets to the Xara Designer Pro X365 version 12 key listed on my Magix account and ignores the Xara Designer Pro X (15.1) humble key which is also listed in my Magix account. Doesn't seem to be any way to change it. Maybe we just wait a day or so.
Anyway, thanks for looking into it Rob.
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