Hi There @Tagdog
You can see the required WordPress file permissions here (https://codex.wordpress.org/Changing_File_Permissions). If your changes not getting affected, please contact your hosting provider to resolve the issue.
By the way, you need the latest version of X theme and Cornerstone plugin to run your validation for the first time. You can download the latest version of X theme from your Enavato account and re-install your X theme by simply deleting the existing X theme. All your current data will be saved in the database.
For validation to function correctly, you need PHP cURL extension enabled on your server and also make sure that your server's firewall is not disabling requests from theme.co. You can see our troubleshooting guide here (https://theme.co/apex/forum/t/troubleshooting-validation-connection-issues/201).
Also make sure that you're using PHP v5.6.x or later to avoid incompatibility issues.
If you require further assistance, provide us with your WordPress credentials along with your FTP credentials in a secure note to investigate your issue further.