Hello, O2DCA,
Thank you for contacting us and for using XStore.
Downgrade the PHP version solves this problem with the current theme version, in the next XStore update, we will add compatibility with PHP 8.1 – https://xstore.8theme.com/update-history/
If you have any additional questions or concerns, please do not hesitate to reach out to us. Our support team is always available to assist you.
Kind Regards,
8theme team
One standard license is valid only for 1 project. Running multiple projects on a single license is a copyright violation.