Hi,
unfortunatelly only about 2-3 % of buyers leaves ratings. At least this is my experience. I don't know if this because they don't care or because it's rather difficult to find where that rating feature is located (AFAIK it is buried deep in menu), or combination of both. I wish that buyer ratings would be much more prominent feature of CGT, like it is on ebay. I tried to rise this issue in the forum for a couple of times, but it looks like it's not interesting neither to CGT staff nor to designers themselves.