Ollie doesn't hang around here much these days. Note the date on the last reply.

There's a ton of good info out at various spots on the 'net. Just google for "flying wing" and you'll find lots of sites with good info.

In particular there's something called the Panknin wing twist formula that is very useful for determining the amount of twist needed for swept flying wings. It can also be used to find the best CG for a plank style wing as well if you"trick" it by inputing a very shallow sweep angle and then move the CG back and forth until the twist is zero or near to it. This equation has been inputed into a spreadsheet and you can find it at www.b2streamlines.com along with some other great flying wing info.