I set up Quickfile, and it is really fantastic. Thanks for it!

But I have some trouble getting it work. Paypal Sandbox seems to be OK, I configured the "Instant Payment Notification Preferences" as well as the "Website Payment Preferences" as suggested, and there are the completed transactions over there, I have also a download link in my site, but the link does not work, it launches at the download error page. http://www.example.com/quickfile/download/5TF70895MD5137441/10/paypal

1. Can I be sure, that the Quickfile directory has been set up correctly, when I am adding a new quickfile content, the autocomplete works in "File Path" field? I mean it lists all the file names copied to quickfile directory.

2. There are no transactions logged in my site. The Transactions page, as well as the transactions table in the database is empty. Can you give any hints what to check?