We've been using the DownloadsII add-on for a couple of months now and it is working great. Thank you. You can check it out by clicking on the navigation bar "Downloads" link at the top of the following vBulletin based forum:
http://www.flexsim.com/forum/index.php?
It's an open area without a login required.
The only thing I wish it had more was permissions by usergroup, but I see that is coming soon.
Cliff