The design of autoreleased shared CBPerl does not agree with the common usage.
Do you plan to allow multiple instances of CBPerl's each having its own interpreter? AFAIU, some parts of the code seem to consider this eventuality.
Support for multiple CBPerl instances is the long-term plan. But, Jaguar's perl wasn't built with multiplicity enabled, so it's on the back burner until Jaguar falls below the radar.
I agree that the autorelease design isn't ideal - I intend to address both of these issues in the next release.