Alright, Thanks for sharing the access with us and for the other details as well.
The thing is that the issue appears because the theme is updated but the core plugin is not so the theme functionality will not work as expected. You said that whenever you update the plugin critical problem starts appearing on the site so there must be a plugin issue or customization if you added in the theme. So in order to solve both issues (Fake viewing and XSTORE Core plugin) follow the below steps.
1) Remove all the customization from the theme if you added.
2) Disable all the third-party plugins including cache plugins. Just enable the theme packaged plugins.
3) Then update the XSTORE Core plugin and then first check back to your issue by clearing the browser cache. It will be resolved.
4) Then activate the third-party plugins one by one.
5) After that you can again add the customization in the theme if you added it.
Regarding the variation issue once you update the plugin and disable all the third-party plugins this issue will be resolved also.
Regards 8Themes Team.