hi Frederick, i can see that this is still a hot topic as the last post was 5 hours ago.
i'm also getting the error when i try to set up the pull zone: (box in red at the top of the W3 dashboard:
"A configuration issue prevents CDN from working: The "Replace default hostname with" field cannot be empty.You need to select / create a pull zone. Specify it here.:
the error when i go to the CDN is the following
Fatal error: Cannot redeclare class OAuthException in /home/brightsp/public_html/mysite.com/wp-content/plugins/w3-total-cache/lib/OAuth/OAuth.php on line 0
please note that i'm using the latest version of WP, but in my case i have a multisite installation with domain mapping... not sure what/how this will affect things, but worth mentioning