I am a exe developer, not a web developer, so am not used to working with htaccess files.

For about 2 months, during our spare time, my wife and I were developing her site (she was adding the pictures and text, I was tweaking the php). During that time, the main htaccess file (at same sub-directory level as zp_data and themes) contained "RewriteBase /~pixmixca/photos" and we accessed all the pages as admin from 199.16.152.234/~pixmixca/photos/.

When we went live a week ago, the pages were not working and so our ISP host changed the line in the htaccess file to: "RewriteBase /photos".

Now, when we (or the public) connect, all the pages work. But, of course, neither the unpublished items nor the admin menu show. We can still access http://199.16.152.234/~pixmixca/photos/, but whenever we click anywhere from there (to an album, page, etc), we get a 404 error - for example: "404 Not Found The server can not find the requested page: 199.16.152.234/~pixmixca/photos/page/contact (port 80)".

We would like to view various pages and images without incrementing the hit counters. And we would like to try creating a dynamic album. For both, we need to be able to view the site as admin.

I'm sure a simple change to the htaccess file is all that is needed, but I could not figure what, even after reading everything I could find related to htaccess in the user guide and the forum.

Any hints at pointing me in the right direction would be appreciated.

The rewrite base is important. Just re-run the setup script to fix that for you.
But you have to decided how you wish to access your Zenphoto install.

If it is 199.16.152.234/~pixmixca/photos/ the rewrite base must be /~pixmixca/photos/
If it is www.domain.com/photos is is /photos
If it is directly under a domain www.domain.com the rewrite base is just /. No matter if the actual folder is named /photos and the domain just links to it. The webpath via the browser is important.