Great forum. I'll try and help out here from time to time.
Here's a request: a unique location or name for the zenphoto admin login cookie.
Right now, if you log in to the demo on your site, and then try logging in to your own installation, it conflicts, and I think it's because the cookie is stored in the root and simply called "zenphoto".
I think it would solve a few problem if this cookie was somehow unique to each installation. Also in cases where there are several ZP installations on the same server, like on my site. In my case it doesn't matter much, since the login/pass is the same, but you catch my drift.