Like I've earlier stated on our own forums, FDF Mod Repository in its older form was quite unusable and taking too much resources to manage, therefore it was taken down on purpose. So far I haven't had enough time to code new version or fix older one.
But oh noes. I got an idea. Let's make those files available. If you want, you can go browsing the missions and campaigns at "temporary" repository. Not sorted, not described, no guarantee at all -- for now, I might code some quick fix. You might figure out game mode and island from filename or maybe there's readme inside. If you got problems, you might try posting at our forums. If you want your missions there too, mail them to firstname.lastname@example.org or PM me. Same goes for all ideas etc.
tl;dr repository files @ "temporary" repository
Edit: I play FDF on OFP more often than on ArmA I or II. Nothing beats the winter WW2 feeling. It's shame we didn't get 1.41 released. Sometimes (like a couple of weeks ago) I have kind of urge to start working on it again. Also FW200 could finish his stuff, krhm krhm :D