Good Job Vision 2012, I started with the old method some years back, stitching and removing the outer skinned foam was a pain in the Butt, I tried a number of different methods, but in the end gave it away. Steve Rahm the designer said that 1/4" was strong enough for the entire Airframe but it made it difficult to maintain the desired shape, and as you pointed out, transferring to another Jig for the internal glassing had it's problems as well.
I tried bending the foam to give a more rounded fuselage shape, narrow at the Butt 40" and wider at shoulders 44", but when I cut the string it all sprung out as the 1/2" wanted to return to it's original form. I could see the issues with the Fold-a-frame method and gave it away. I have since designed my own Plane, but getting too old to build it on a Pension,
I did run the numbers for the Vision, they all stood up pretty well, Steve including his father had a lot of History in Aviation and to him being safe was of significant importance - nothing was recommended unless built and tested. I tried for ages to get Steve to develop a Carbon Spar to get weight down to Light Sport, alas to no avail - now it's available through Scott, but too late for me.
All the best with the rest of the development.
George