Hello zenphoto, I just installed this great software today.
I had some difficulty with thumbnails in my theme and decided to write a patch to fix the problem. I hope someone could let me know if I did this in the right format for you.
http://www.zenphoto.org/trac/ticket/579
The one thing I'm not familiar with is where function getImageParameters() might be used in other places in the code base. It would be good to know if I broke something else by fixing this.