I remember when this first came out. I was a member of the E.A.A. for many years. I read up on the R/C kit that kit being sold and I remember something I was surprised to read, "watch out for PIO, and you should not have any problems with flight", something like that, not an exact quote, bit I remember thinking to myself that that plane is so short, it looked like it could be susceptible to "Pilot Induced oscillation", and the R/C version is, also, supposedly it can do flat spins, I would like to see how it exists them. I am not a fan of aircraft that have no rudder authority from the propeller wash, as a measure of control is lost. I remember also reading that there was not much here that was not offered by other well proven designs. That may be why 25 years later nothing has been done with it. It was supposedly supposed to be an "open source" design, but ironically, no plans are available, but information is sought, and a company has been licensed to sell the "open source' R/C version. I have seen other planes with this type of wing configuration, though I think the rear wing usually hand an anhedral and this one has a diehedral.
You should making one out of foam sheet, it would be relatively easy and probably just as easy to make an R/C version using micro servos and an electric motor. C.G. wouldn't be hard to figure out, just make sure it's ahead of the center of lift!