I am using the CDN with great success but I was wondering if it's possible to only use the CDN path for specific paths... For example I use K2 and I only want the K2 images to be served from the CDN. Is it possible to set only specific paths to be replaced? (For example only paths/files from the /media folder)
And is it possible to re add the option to also use the CDN in Admin?
No there is nothing in the CDN for Joomla! code that concerns enabling in the admin. It has never been an option.
There is an $_enable_in_admin property in the global SystemPlugin class used by all Regular Labs plugin extensions. But that is not used by CDN for Joomla!