Just a little more info on how to update your plugin-
You should be able to go to “My Account” and then see your available downloads from your purchases. That link for the plugin should already be the new version, so just go ahead and download it from there to update.
Note: Your WP-Admin will not show the typical automatic “update” link in your plugin list, you need to deactivate and remove / delete the old plugin from your plugin list, and then upload the new one from your download link in your account page.
Let me know if you have any issues with this. I can also email you the zip file if you have any issues.