Hi,
the rating is connected with a document, in the
CMS_Document table there is a
DocumentRatings column and
DocumentRatingValue column. As I said, this value is connected with a document, in your case with a product document and the featured product does not seem to contain the value. I am not sure how you inherited the content from the parent product, but the rating does not seem to be a part of featured product. It is not indexed by the analyzer, therefore your transformation function does not seems to return correct value. You could create a custom field in a featured product document type and inherit the content from the parent. Then the value would be indexed. Alternatively, you could move the rating web part on a featured document.
Maybe, you could create a
custom transformation function with parentID parameter (it is probably available in a featured product), and get appropriate value using
document API.
If you would like to make this rating field searchable on the featured document (not only display the value), you can take a look at this
thread.
Best regards,
Ivana Tomanickova