Amazon Seller Fulfilled Prime is becoming more and more popular. In Storefeeder to handle the prime orders, you do need to set up an Amazon Logistics integration because the one thing Amazon does require is that you purchase your label for prime orders through them. The amazon logistics integration will return you either amazon logistics or royal mail labels depending on what you have enabled on Amazon.
To make a listing a prime listing you just change the shipping template against the listing - if you manage your listings through StoreFeeder the field is called "Shipping Group Name" in StoreFeeder. To download the shipping template we need to download a listing with the template. If you put the template on one of your listings on amazon directly and then redownload the listing we will grab the template when we get the listing back into StoreFeeder.
We have an in-depth guide on integrating with Amazon logistics here
And once you have the integration set up the next set is to alter your shipping rules for the new prime orders so they picked up correctly, for prime orders we mark the orders with a prime flag and this can be used in shipping rules now so we suggest you set your rules up using this flag to easily pick up the prime.
We have a guide on how shipping rules are set up here