Jim -
Here is some very good info. (you have to ignore how over-the-top upbeat they are):
http://www.gonewiththewynns.com/composting-toilet
http://www.gonewiththewynns.co...toilet-big-questions
http://www.gonewiththewynns.co...-fleetwood-excursion
http://www.gonewiththewynns.co...cks-solving-problems
http://www.gonewiththewynns.co...e-rv-black-grey-tank