With Filestar you get 22 different skills for working productively with Compact Pro Archive (.cpt) files.
About .Cpt
Name
Compact Pro Archive
Extension
.cpt
Format
Binary
Category
Compressed
Developer
Bill Goodman
Description
Compact Pro Archive (.cpt) is a compressed archive format used on classic Mac OS, created by the Compact Pro compression utility. It bundles multiple Macintosh files—including resource forks—into a single compressed archive, and served as a popular alternative to StuffIt in the early 1990s.