I have fixed my problem. It appears to be an install issue.

Our calls to the module were being resolved by modules bundled in the build by ActiveState which were not up to date.
When I queried the version in ppm it was reported that Archive-Zip was not installed.
I installed Archive-Zip and now my script runs to completion.
We had never installed the module since we never had issues with the calls.

Thanks for your response. (I hope this helps others with similar symptoms but not necessarily this module.)