Hi There @BBLaser
Thanks for writing in! The WordPress user that you have created, does not have enough permission to check your site. Could you please grant administrator privileges to that user, so that we can check your issue.
In the meantime, try downloading the latest version of X theme from your Envato account, delete your current X theme and Cornerstone plugin, then re-install the latest version again and try to validate your site. When you have older versions installed on your site, our validation process will not be initiated correctly.
You can safely delete your X theme and Cornerstone plugin as it will save your current settings in the database.
You can check the latest version numbers from here (https://theme.co/apex/forum/t/troubleshooting-version-compatibility/195) and our update guide from the following link (https://theme.co/apex/forum/t/setup-updating-your-themes-and-plugins/62).
Also I would suggest you to check the validation troubleshooting guide from here (https://theme.co/apex/forum/t/troubleshooting-validation-connection-issues/201).
Let us know how it goes.