User Made Campaigns:

Dragonslayer by Scooter
Graveyard Shift by Scooter
The Ninja Trail by Scooter
Trolls by Scooter
Turner the Rabbit courtesy of Wolfire (http://wolfire.com/)
Tombe des Armes by Nameless Tee

How to install user-made campaigns:

On Windows: Go to C:\Program Files\Rubber Ninjas\data\campaigns and drop the campaign you downloaded there (after unzipping it).

On Macintosh: Right-click (or ctrl-click) on the Rubber Ninjas application icon, chose "show package contents", navigate in contents/resources/data/campaigns and drop the unzipped campaign you downloaded here. 