+1 to the automatic withdrawal

Is it intended that it is not very hard to guess links to files you don't own?

http://www.downloadcoin.com/content.php?dist=__&d=__
dist seems to be a userID, d is most likely just a running file ID. If I now query all "d"s for a fixed "dist", I should have a list of all files uploaded with that bitcoin address...

How long do you store files, even if they never get downloaded? Is some content forbidden? What information do you log of Uploaders and Downloaders? How do I delete files again, if I want to?