There is an ongoing outage on the primary CPAN mirror. It is possible to work around the issue by using MetaCPAN as a mirror.

2020.06.21 (a*|b+) was accepting a b, now it does not,
2020.10.30 Available on GitHub - see "How To Contribute"

2020-10-30 Now available on GitHub at: https://github.com/philiprbrenan/DataNFA
           Please create a pull request from a cloned copy.