That's what I was wondering as well. I'm not sure how the lightbox script would find the images without displaying them. Perhaps ZPP could attach the images to a particular post via the media gallery table without displaying them.
I'm currently doing something similar (not attaching images, but displaying a text link) with a Gallery2 plugin that authenticates using 'Gallery Remote', but I didn't write the plugin. Plugin pulls the images in and displays them on a plugin options page. A custom field on the post level designates the exact album.
Here is a live example of that functionality.
Might be a cool feature for a future release. I use a text link often since we embed gallery links into posts that tend to have a lot of bulk already and we are linking to somewhat large albums.
Thanks so much for all of your help. :)