It sounds like you have set up your CDN slightly wrong.

After setting up a few like you have I realised that I was actually making a complete duplicate of the site rather than just the images or assets

I imagine you have your origin directory for the CDN in the public html folder.

Create a subdomain, set that as the origin.

Eg.. I'm working on this site at the moment: http://looksfishy.co.uk/

I have a subdomain called assets: http://assets.looksfishy.co.uk/

The cdn content: http://cdn.looksfishy.co.uk/

Files uploaded here:

http://assets.looksfishy.co.uk/species/holder/pike.jpg

Displayed here:

http://cdn.looksfishy.co.uk/species/holder/pike.jpg

Check the ip address on them.

It does make uploading images by ftp a bit of a faff, but does make your site better

I think thats it's kind of ironic how long it takes to get listed in DMOZ..

I know lots and lots of people who havent been able to get listed in there... but then you look at some of the sites that are in there and they are complete garbage!