RewriteEngine on
RewriteCond %{REQUEST_URI} !^/_wpez18/
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ /_wpez18/$1
RewriteCond %{HTTP_HOST} ^(www.)?occcustomsite.com$ [NC]
RewriteRule ^(/)?$ _wpez18/index.php [L]
ErrorDocument 404 /_wpez18/index.php?error=404