That text file idea is good!
If the text file is there in the album directory, with the name of the main image "imagename.jpg.txt" then underneath the main image (or where ever I put the get related images php) the mini thumbs show up or the numbers show up (which is better? - I think the numbers that can be styled with css or background images or something, loads faster).
The album name "flower paintings" has a bunch of images in it and then related images, the flower flowermain.jpg, flower1.jpg, flower2.jpg, etc., only the related images would go into another directory inside the main album so that ZP doesn't make a thumb of the related images.
flowermain.jpg
related/flower1.jpg
related/flower2.jpg
related/flower3.jpg
Mini thumbs would be sized by hand and located in this related directory:
related/flower1_mini.jpg - hand sized (no GD functionality required)
I can follow naming the files the same and with _mini.jpg so that this add on will not be a bitch to implement.
My main purpose for this is that I make web sites for artists and architects (start ups) with not a lot of money, but they too should have the ability to maintain their own stuff. ZenPhoto rocks. It's so simple and I love that I can skin it easily.
Here's what I mean on how it would work:
http://www.squidfingers.com/work/ This is not my site BTW. I am not as good as he is.
How much do you charge per hour and how many hours do you think it will take? I don't want to short change you and, since I have no clue how to do this myself, I don't know how long it would take. When 2.0 comes out, will this extension work with it?
Thanks!