Another question... In my testing... this mod wants to override the following core files:

admin/includes/modules/category_product_listing.php
includes/modules/additional_images.php
includes/modules/main_product_image.php
includes/modules/pages/popup_image/header_php.php
includes/modules/pages/popup_image_additional/header_php.php
includes/templates/template_default/popup_image_additional/tpl_main_page.php

These core files in the Image Handler download (Version 2.0 rev 7) are NOT based on the core 1.3.8a files and I am having a difficult time trying to figure out what is Image Handler code (no comments or identifiers that I can find in some of the files) and what is old code removed or updated in the core 1.3.8a files.

Just one example: includes/modules/main_product_image.php is drastically different than the latest zc core file and there is no mention of anything Image Handler in there.

Yes, I am clueless on what is image handler modified code.