Here is some info from "The Bow Concept" in the news section.
The main innovation consisted in putting sweep, i.e. to move back the wing tips compared to its centre until the trailing edge is concave, which makes it possible to flatten and perfectly tighten this one. This is associated to an original and very simple bridle device, only fixed on the leading edge, conceived to allow almost full depower and a great turn speed.
Swept-back + simple bridling on the leading edge only, here is what differentiates the BOW concept from all other flat wings.
Many alternatives of planforms and bridles are possible inside this concept. Thus the Nova such as it is presented today was developed by the Takoon designer, Nicolas Caillou and has a different form from the Nova exposed to the Paris Boat Show in December 2004 and which was a Legaignoux design.
phpbb/news_show.php?m_id=140
and
http://www.grc.nasa.gov/WWW/K-12/airplane/kitefor.html
Ed