SHIPMENT FOR VIRTUAL PRODUCTS: multiple items one product

[rtringo]

I have installed the SHIPMENT FOR VIRTUAL PRODUCTS plugin and all is working well. How to I add multiple mp3's files to a single purchase item.

For example I have 10 songs that I want to sell as one title (Product). I see how to add one song to the title but not how to add additional songs so that the customer on makes one purchase for 10 songs.