I've just submitted v2.0.1 to the Zen Cart plugins for review. That version contains changes for:
  • Changing the number of ZipShip "zones" doesn't clean up previous settings.
  • US Zip Codes entered in 99999-9999 format don't result in a match.
  • Remove unused configuration setting (Skip Zipcodes)
  • Add an overall zone setting for the shipping method.

Please note that this version makes use of the store's Configuration->Minimum Values->Post Codes value in its processing, truncating an order's ship-to zipcode to that minimum length prior to look-up in the ZipShip configuration. Any zip/post code entered is also uppercased prior to lookup; potentially making this plugin more useful on stores where the postcode is an alphanumeric value rather than simply numeric.

The plugin release is currently available on the plugin's GitHub repository: https://github.com/lat9/zipship/releases/tag/v2.0.1