Hi Guys,
Nice work Al.
with regards to release, you have Dakota's blessing above, and over the years while doing work for other addons we have had permission from Corado, Ed Wilson, and a whole heap of other guys who worked on everything from Korean skies through to Rising sun, to modify original works to improve the existing addons, and to include this work into new addons. (It was actually one of Ed's list of of things to do (update KS), but sadly he never had the oppurtunity.)
The only exception to this was the MAW addon, I got permissions to work on some of the aircraft and include them where required but we failed to get permission to make banket changes from the whole team, so MAW sits as it stands at version 1.10 (bit of a shame really)
I do not think there would be one person get upset if you were to release your files as an update for people to install. If people dont want to install it they dont have to download it. Youre not replacing the original download files in the Korean Skies addon your supplying alternate files for people to try if they want to.
thats just my 2 cents,
regards Rob.