Just submitted v1.3.1 for part 1, which is an update of SQL file for Japanese postal codes when no zone is defined for Japan.
Postcode auto fill Part 1
Part 2 does not need to be updated, please use v1.3.
Postcode auto fill Part 2

This release is probably the last one for Zen Cart 1.5.8a. A new version for ZC V2.0.0 will be there soon.