The following will help you create custom feed rules to use imported Amazon data.
1. Product images
Unfortunately, images from Amazon's ASIN lookup API are returned as URLs to images with a size typically no larger than 500px.
MAP image_link TO SmallImage_URL
Example Image URL: https://m.media-amazon.com/images/I/41PQ6SUjm2L.jpg
2. Product URL (Amazon product page)
Use a custom feed rule to build product URLs to the Amazon product page by concatenating the base URL with the ASIN like this:
SET link TO https://www.amazon.com/dp/ + [P].[asin1] when asin1 is not empty
3. Product Type (Amazon category)
Amazon gives us two category levels ProductGroup and ProductTypeName. Use a custom feed rule to combine them together with a breadcrumb caret like this:
SET product_type TO [P].[ProductGroup] + " > " + [P].[ProductTypeName] WHEN both are not empty
4. GTIN / UPC from product-id
Amazon will sometimes provide the UPCs of products. Amazon identifies the GTIN or UPC as ProductId = 3. Use a custom rule to conditionally set them to the feed GTIN field.
SET gtin TO product-id WHEN product-id-type equals "3"
5. Description to use Titles if empty
If the description is missing from the Amazon data import, then simply use a custom feed rule to set the product titles as the description to get around channel requirements if the description is required by the channel.
SET description TO title WHEN description is empty
5. Other attributes
Lastly, be sure to examine all other attributes that were imported from the Amazon API. Different products may return different attributes that may be useful to map into your export feeds.