The no groups error usually comes from lacking comps.xml in the
repository metadata. Revisor uses that comps to create the list of
Categories and Groups during package selection.
Grumble. I'm using mrepo to build my repository. It's great except that
it seems to ignore the comps.xml file on the source repository. In
futzing around, I found out (FWIW) that Resolver (or anything else hitting
your repo) finds the comps.xml file by looking in the repomd.xml file. I
was able to solve the problem by copying the comparable section out of the
repomd.xml on the official fedora repository into my repomd.xml. Then, it
was just a matter of making sure the path, etc., in that section were
correct for my repo.
regards, Tim