Please refer to the Uninstall section in this topic.
You App Store license is synchronized as long as you have iCloud enabled, so theoretically you don't have to install App Store version first.
If your App Store version of Core Tunnel has sync enabled, you need to wait awhile to let iCloud sync data to the Codinn Store version.
Reinstall App Store version, and export profiles to a file if iCloud sync gets glitch.
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