In Account Info, there is a new link in Profile Settings labelled Export eCommerce Custom data. When clicked a zip file will be downloaded, containing 3 files:
Client_Import_Product_Mapping.csv - Associates products from import #1 to categories on the webstore.
Private_Catalog_Import_Products.csv - Holds all product details, images, variations etc. for custom eCommerce data.
Client_Import_Shelf_Quantities.csv - Sets the sale price & available of a product from import #1.
This new feature will mainly be used to export existing Endeavor eCommerce data into PSS.