Using a CDN for static content

[Roonis]

The first part went with out a hitch. Many thanks!

but the second part is not yielding the results im looking for. I added the script as seen below.

function write_css_file($filename, $contents)
{
$contents = process_replacement_vars($contents);
// attempt to write new css file - store in database if unable to write file
if ($fp = @fopen(DIR . "/$filename", 'wb') AND !is_demo_mode())
{

And i used the rewrites exactly as posted
When i turn on the store css sheets as files on and off the links in the files are still the old forum links. NOT the cdn links

Any ideas??