miska,
sounds very nice,

write all the changes you made into a readme.txt file,
(you don't have to be totally specific with by how much you increased the thresh-holds, if people want to investigate that they can compare your version with the standard one)

Then add all the files you changed and the readme file to a zip file and upload your campaign tweaks to the org,
http://www.totalwar.org/site/upload.php3


What you have made is a mod, and we would be happy to host it for other players to download and enjoy.
:-)
Barocca