Site Background file not processed by GD Booster?

Hello,

My site background file set in GDF Options (Heading Styling Options > Header Background, & Body Styling Options > Body Background) is being flagged under several headings under Pingdom test:

1. Minimize Request Size – where it is listed separately as served from my domain servers not MaxCDN servers;
2. Leverage Browser Caching (it appears not to be cached as a static resource – as I thought static resources are by GD Booster)
3. Serve Static Content from a Cookieless Domain (again, where it is not coming via MaxCDN servers)

Is this an issue with MaxCDN operation – or is it just not being processed properly by GD Booster?

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