I would like to be able to sell music, is that possible with this?

Actually, that feature is already built into th software... you have the option to upload a file with the product as you add them into the store. this could be either music, video files, pdf's e-books, etc.

When a customer purchases, we let them download, and in this new version 6 you can control for how many days that occurs AND/OR the length of time you want downloads available.

in the admin console, we also set it up so you could reset those figures for a customer, if for example they went over their download limit and contact you for another download.

of course because it's built in flash, you could incorporate all kinds of custom things such as demo players, movie systems, etc.