Is there any validity to the skin carotenoid scores by pharmanex biophotonic scanner? what does it do/indicate?

Highly unlikely.: There is no third-party research that supports the claims made by the company. All claims come either from the company itself or the few places that have one of these machines. Furthermore there is no proof that high levels of antioxidant in your body is better for you. This is just another way to get you to buy vitamin supplements. Don't waste your money.