Most probably CPANTS databases are being regenerated from scratch due to major changes in Kwalitee metrics or updates of relevant modules/perl. Usually this maintenance takes about a day or two, and some of the information may be old or missing tentatively. Sorry for the inconvenience.
Add a META.yml to the distribution. Your buildtool should be able to autogenerate it.
Remove the offending files/directories!
Error: Makefile, pm_to_blib
Update MANIFEST.SKIP to exclude MYMETA files. If you are lazy, add "#!install_default" in your MANIFEST.SKIP and update your ExtUtils::Manifest if necessary, then some of the most common files will be excluded.
Run a proper command ("make manifest" or "./Build manifest", maybe with a force option), or use a distribution builder to generate the MANIFEST. Or update MANIFEST manually.
Error:
List all used modules in META.yml requires
Error:
Make sure that the main module name and version are the same of the distribution.
Add a META.json to the distribution. Your buildtool should be able to autogenerate it.
Move your *.pm files in a directory named 'lib'. The directory structure should look like 'lib/Your/Module.pm' for a module named 'Your::Module'. If you need to provide additional files, e.g. for testing, that should not be considered for Kwalitee, then you should look at the 'provides' map in META.yml to limit the files scanned; or use the 'no_index' map to exclude parts of the distribution.
Error: blib/lib/Tk/Markdown.pm
Define the license if you are using in Build.PL. If you are using MakeMaker (Makefile.PL) you should upgrade to ExtUtils::MakeMaker version 6.31.
Add all modules contained in this distribution to the META.yml field 'provides'. Module::Build or Dist::Zilla::Plugin::MetaProvides do this automatically for you.
Add a 'repository' resource to the META.yml via 'meta_add' accessor (for Module::Build) or META_ADD parameter (for ExtUtils::MakeMaker).
This is not a critical issue. Currently mainly informative for the CPANTS authors. It might be removed later.