NOTE: Require In-Commerce module to be installed.
# login to the Admin Console
# go to the {nav Website & Content > Structure & Data > Products} section (you should be on the `Products` tab)
# switch to the `Sections` tab
# add a `Sub Products` section (category)
# go to the {nav Website & Content > Structure & Data > Products > Sub Products} section (you should be on the `Products` tab)
# create a downloadable product in Active status with 1 file in it
# login to the Front-End
# go to the `Products > Sub Products` category and buy above-created product
# go to the Admin Console
# go to the {anv E-commerce > Orders} section (you should be on the `Pending` tab)
# confirm, that just submitted sales order is shown in there
# select just submitted sales order
# click on the `Approve` toolbar button
# confirm, that the sales order is longer shown in the Pending orders grid
# go to the Front-End
# click on the `My Downloads` link in the side bar
# click the `Download Now` toolbar button
# confirm, that downloaded file matches (by content) the file used when creating a downloadable product