I saw this further back in the post history, but thought it might need further investigation. I've tried enabling everything I can find relating to allowing a customer to place an order, (free or otherwise), for a downloadable product and so far, all I can get is a templated page, from within the order status page and click the "download url" link. I'm sure I've checked everthing at least twice and with the help of a friend, have had them "order" a small zipped file from me and neither of us can seem to get that function to work. The link shows up in the email that gets sent, but once clicked, it takes them to a "blank" page and no hint of being able to aquire the file/product. I've even added the updated file mentioned in the previous message, but already have the most recent version of the package. Thank you for your time.

I feel your pain. Same story here. I tried the fixes suggested by the admin in the previous posts and have tried every combination of url you can imagine i.e. using or not using http://mysite/etc and /shop/etc and so on. No luck. Got a nice email from support, but it did not solve problem. Want to buy but this is killing me.
 
Instead of blank page get pretty viart template with messages either product inactive or product cannot be found. This even happens when I enable that particular order to be downloaded, as suggested by admin.