Photos, drawings, and descriptions of outrigger canoes around the world. http://gary.dierking.net
But what are the rigging tweaks?
I believe that the fore and backstay attachment points on the bows have been moved so that the stays are more vertical.
Videos like this render all the millions of words about proa types, theoretical configurations etc. redundant. Just LOOK at how that boat sails - I can't imagine many things come close for simply experiencing the joy of sailing for sailings' sake. I like to imagine that Russ Brown has a qualitative approach design rather than crunching numbers to the nth degree.