A revamped Guide to Perl 5 Embedding is now available. It provides details on how to pass the most common data structures to Perl 5, including arrays and arrayrefs, hashes and hashrefs, strings, and even code references.
Examples of using Perl 5 OO from Perl 6 are also provided. Some related bugs have also been fixed recently in Pugs.
Perl 5 embedding allows you create a project in Perl 6, while still using Perl 5 for parts that have not yet been ported to Perl 6. Updated Perl 5 Embedding is just one of the many updates that will be available in the next release of pugs, expected soon.