the gnustep-nonfsf looks unlucky in its birth! When I use the "Downloads" link I get:
I confirm that https://savannah.nongnu.org/files/?group=gnustep-nonfsf yields a 404 message(*), and that download0:/srv/download/gnustep-nonfsf/ contains some files. I no longer know how all these things are intended to fit together. I hope one of the others can fix can fix ... --sorry, karl. (*) And the message contains a relative url, which should be absolute to be useful.