The long-awaited unofficial community expansion to OFF is now available at Combat Ace
. See the posting for the full list of contributors.
This is a complete package--no other mods or downloads required. It's designed to be easy to use for everyone, with no hassle. But give it plenty of time to install and configure itself on first run as it's 1.7GB of stuff all together.
Notice it's not quite version 1.0. This is a first public beta. With extensive changes to flak, guns, ammo, balloons, etc. it would benefit from testing and feedback from experienced flyers. The incendiary ammo and balloon system still experimental, so consequences for mis-use still are not in place during testing. You're on the honor system for now.
If you go ahead and test how effective it is against airplanes, let us know on the support page
, or if you experience bugs or run into other problems. If you don't want be a part of such experiments, wait a little bit for further refinements.
As always, read the fine print (backup your pilot files--they're now easier to restore than ever). And have fun!