Maybe this will get an answer, it got lost in some other thread. (I can't even find it myself)
http://www.shop-script.com/demo/I ran a small tool store with their free demo for awhile. It seemed well written. The price and database changes I made with CSV files and then uploaded. Runs php, not dependent on some other software.
The whole digital products part is kind of vague. I asked and I still don't know how well it manages then.
Anyone know more? I guess it's time to write support again.