I switched to ZenPage theme and activated the related extension. But when I select the Page that appear, I get the error that the ZenPage object could not be found... :-(

Do you have a link maybe?

This is inside the Administration zone... Galleries are private (family). I cannot open the site to public.

One word was missing in my post:

... when I select the Page tab that appear...

So the "pages" tab on hte backend does not work? I have never seen or heard of. What Zenphoto release btw? Any errors in the server error log?

I'm using the following version:

Version de Zenphoto 1.4.1.6 [8326] (Version officielle)
Paramètre régional présentement utilisé : fr_FR.UTF8
Thème actuellement utilisé : Zenpage
Version de PHP : 5.3.6
Bibliothèque graphique : PHP GD library bundled (2.0.34 compatible)
MySQL version : 5.0.92

When I select the Pages tab (or the Pages option in the ZenPage theme menu) I got to:

.../zp-core/zp-extensions/zenpage/admin-pages.php

And get the following error:

L’objet Zenphoto demandé n’a pu être trouvé.
Album: zp-core/zp-extensions/zenpage
Image: admin-pages

I have no idea, sorry, that should not happen. Maybe my collegue later as any.

:-(

Isn't here a permission problem?

It might be a permission problem. So again is there an error in the server error log? The error above is a Zenphoto (a front and one actually that should not appear on the backend at all).

The above error can occur only if the zenpage script admin-pages.php is missing or not accessable. So this is some kind of installation issue.