Hi Matt,
Some comments (hopefully final):
1-A Windows version of feff85L (called FEFF8-Lite) is freely available, with some other codes, at
http://leonardo.phys.washingto
n.edu/feff/Bin-Source- feff8Lite/Bin-Source.html
One can also find the feff85L.f source code in other places.
2-Being able to generate automatically with Artemis an input file for feff8 is of course convenient, even if one would have to enter by hand some keywords (e.g. SCF) to get the full functionality. I did this, added into Artemis the so modified feff.inp file and tried to run feff8 with that file. I found a message saying "You are running Feff8 with self-consistent potentials.It WILL be time consuming and all interaction with Artemis will be blocked until the Feff calculation is done. Currently Artemis does not provide real-time feedback, so you will have to be very patient." I would say that gives the impression that Feff8 can indeed be used within Artemis. Indeed you say "Artemis has been able to use various versions of Feff8 for a very long time". Is it still possible?
3-I do have (properly licensed) feff 9, and indeed have its documentation independently of Demeter. On the other hand, unless one has an illegal copy of feff 9 I do not see the usefulness of having that documentation without having a license.
4-Unfortunately I am not competent enough as programmer. I would not be able to contribute to make Artemis able to use feff8 calculations. If you have not time to devote to it, I fully understand it. Already what has been done in Demeter is a great work.