Well, i'm downloading for rfactorcentral too. i guess if something it isn't there it doesn't exists, right? because i've searched like the whole internet for a Ferrari 348 or F355 Challenge mod without success.
Now, what's you preferred method for managing mods: separate installs, or keeping everything on a big installation and using a mod manager?
i'm using the first option even when sometimes it means having duplicated racetracks for each one of them.
The other thing i would like to know is if is out there some external program to browse the multiplayer servers better than the in-game browser, because that's the bigger cluster-you-know-what i've ever seen.