I don't know if this behaviour is reported:

Case:
There is an album with an "invisible" File inside. E.g. ".picasa"
You delete this album via the zenphoto admin interface
Zenphoto won't delete this Album because of the ".picasa" file.
Permissions for Zenphoto Folders crash to "666", causing the whole backend to be not reachable anymore.

You can only fix this by manually setting the permissions back to 755 via ftp (which is surely not a suitable solution for everyone).

If I remember correctly that has been corrected meanwhile. Are you really using the current release or even the support build?

Sorry id did happen on a website i did with zenphoto.
The release is 1.4.4 and should propably be updated!

If this bug is already fixed, i'm sorry for wasting your time :-)

1.4.4 was a while ago :-) Best you update the site in question and let us know so we can be sure it is really fixed.