I've been using Zenphoto a few years, and Apache 2 longer, though I am not a network/WWW/IT professional, only a computer scientist in other areas. The instructions to use Apache 2 mod_rewrite are pretty vague/incomplete. Are there any detailed/complete instructions? I run my own server, so I'm not paying someone to set up mod_rewrite details in .htaccess, rather than httpd.conf, that haven't been specified in the instructions or perhaps older forum posts... but if there's a sufficient explanation, I have no problem doing so.
Actually you don't need to do anything specific. What are your specific problems?
If your server is mod_rewrite capable, you don't need to do much. Zenphoto will recognize that on running setup and will offer to respectively setup the require .htacces file. Also within /zp-core there is a htaccess template to copy manually to the root of the install if for unknow reasons setup would not do it.
Additionally you need to enable mod_rewrite/rewritten urls on Options > Gallery > Url options if for some reason not set (will naturally not work if there is no valid htaccess file).
Apparently the problem is I have mod_rewrite but Zenphoto didn't detect it. I don't even know if I have to write anything in httpd.conf (other than of course uncommenting the line to load mod_rewrite, and restarting) or another .conf (such as extra/httpd-vhosts.conf) to activate it.
And, after some reading... apparently you do have to do something specific: a certain AllowOverride statement so that the Zenphoto directory is allowed to use apparently the .htaccess where the setup is done ‘automatically’... that's exactly the sort of thing I was talking about that isn't documented.
Sorry for your problems. I cannot help with server configuration itself as that is out of my expertise. I am/was not aware we do anything specific. After having installed Zenphoto on quite a variety of standard shared hosts based on Apache I never encountered anything similar.
A lot of people use that rather than shared hosting.
Not in my impression and experience, all sites I personally ever setup with Zenphoto was shared hosting. And even our site is on shared hosting.
Zenphoto pragmatically tests a rewritten URL on setup and if it works it works.