Pack the distribution with a proper command such as "make dist" and "./Build dist", or use a distribution builder such as Dist::Zilla, Dist::Milla, Minilla.
Take a look at the META.yml Spec at http://module-build.sourceforge.net/META-spec-v1.4.html (for version 1.4) or http://search.cpan.org/perldoc?CPAN::Meta::Spec (for version 2), and change your META.yml accordingly.
Error: Expected a list structure (author) [Validation: 1.4];value is an undefined string (generated_by) [Validation: 1.4]
Add a META.json to the distribution. Your buildtool should be able to autogenerate it.
This is not a critical issue. Currently mainly informative for the CPANTS authors. It might be removed later.
|Tie::Wx::Widget||get and set main value of a Wx widget with less syntax and more magic||1.0||metacpan|