Right, there's not much to update for something that works across the versions. Starting around this thread: https://www.zen-cart.com/showthread....53#post1236553 the issues with the javascript are described. Now I've tried to look elsewhere/further for any more of a centralized discussion, possibly outside this thread, but as pointed out a page or so ago by lat9, there was a cap on full functionality based on jquery version. After a certain point it just didn't work anymore and the issues seen/described here were identified. That was back in 2013/2014. After repeatedly suggesting redirection to colorbox which I have used the latest found on github with a minor modification to successfully install to a ZC responsive 1.5.5 site.

Niestudio did his homework and testing. He supported both plugins and had identified that it was not worth continuing to develop/modify this module because the base of the functionality was not being worked on/expanded and colorbox base javascript was.