How do I change the default password gallery image (the one that comes with ZenPhoto)?

I know that I can change it by replacing the image or making changes to the zp-core file...but how do I do it without touching either one? I don't want to have to worry about what I replaced or didn't replace when it comes time to update ZenPhoto.

Thanks,
Josh

http://www.zenphoto.org/news/replacing-default-images