Am in transit so cannot provide a complete analysis now. However, please look at line 40 of lib/Parrot/Manifest.pm. This line seems to exclude all file names containing the string 'ports'. While this correctly excludes ports of Parrot, it probably incorrectly excludes all source files with that string in their names.
Andy D's command relies on MANIFEST to copy files to a new location. MANIFEST is made by tools/dev/mk_manifest_and_skip.pl, which in turn relies on Parrot::Manifest. When the t/steps/auto_macports*.t files fail to be copied to the new location, Parrot::Configure::Options::Test barfs because it cannot locate files corresponding to particular config steps. HTH kid51
