I tried it today with a fresh install of Zenphoto Nightbuild from 22th Oktober. I activated the plug-ins register-user, user-groups, user-login-out and zenpage. I use the zenpage-Theme. I didn't used as Gallery password, instead I set the Gallery to private. But when I do this, I can't see anymore my Gallery. Zenphoto allways ask for my username and password. The security-log shows me that the logon was successful (I can go to the Settings etc), but I don't have access to pictures (Gallery) over the index page anymore. If I use direct links (like http://127.0.0.1/test/zenphoto/news/category/rundbriefe or http://127.0.0.1/test/zenphoto/Gallery name) I have access to the news and Gallery (so long as I am logged in). So it seems to me that something is wrong with the index-page.
Thanks for your great work with Zenphoto!