Ubigraph 0.05 Latest
Add a META.yml to the distribution. Your buildtool should be able to autogenerate it.
Upgrade the bundled version of Module::Install to at least 0.89, but preferably to the most current release. Alternatively, you can switch to another build system / installer that does not suffer from this problem. (ExtUtils::MakeMaker, Module::Build both of which have their own set of problems.)
Split the distribution, or fix the version numbers to make them consistent (use the highest version number to avoid version downgrade).
Add a META.json to the distribution. Your buildtool should be able to autogenerate it.
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.
This is not a critical issue. Currently mainly informative for the CPANTS authors. It might be removed later.