Hi Con,

I think that the problem that I have may be that I am using Zen Cart™ Version: v1.3.8a and Zipship has only been updated to Zen Cart™ Version: v1.3.7.

Failing someone updating (I don't have the skills), the only solution I can see is to purchase Ceon Advanced Shipper http://dev.ceon.net/web/zen-cart/advshipper

Alan