It never went beyond notes and pictures during construction. A Google search on Falco kayak will get you all that out there.
Tom was active on the folding kayak bbs also, and posted mostly the same stuff there as here.
There is enuf info there, conceptually, to work out the construction. Get a copy of his website and look at the basic construction for the inflatable Sonnet. The Falco would have enclosed/sliding lock panels instead of sponsons.
The early Falco had the same soft floor with keelson, later he was working on a solid panel design, like the sides.
Or, if thats to daunting, build one of his folders/inflatables.

I join the rest of the world in wishing him well, thanking him for his amazing and excellent work, and hoping hes ok and happy with whatever he's doing.