This wp-admin skip/bypass rule works.
# X Theme CornerStone customize.php skip rule
RewriteCond %{REQUEST_URI} (customize\.php) [NC]
RewriteRule . - [S=2]
The reason it was not working for you is because the Skip rule # was incorrect. By Default there is already a Skip rule in the wp-admin htaccess file. When you add another Skip rule it needs to be S=2. On your particular site you already had a Skip rule so this is the correct wp-admin Custom Code Skip rules for your site.
# Yoast Facebook OpenGraph wp-admin plugin skip/bypass rule
RewriteCond %{QUERY_STRING} page=wpseo_social&key=(.*) [NC]
RewriteRule . - [S=3]
# X Theme CornerStone customize.php skip rule
RewriteCond %{REQUEST_URI} (customize\.php) [NC]
RewriteRule . - [S=2]
Other issues/problems found on this site:
As soon as I logged in I saw this error message, but it only happened when I first logged in: Error reconnecting to the database.
This site has an extremely old BPS Pro version installed. I tried to upgrade BPS Pro using the BPS Pro Upload Zip installer. This server or something installed on this server is blocking/ignoring/not allowing the BPS Pro upload zip installation. Do these installation steps so that you do not have to setup BPS Pro again.
1. Delete the /bulletproof-security/ plugin folder using FTP.
2. Install the BPS Pro 11 zip file using the WordPress Upload Zip installer.
