I'm currently creating a special gallery that call the page 'image.php' inside a thickbox in the 'album' page. The thing, is that I want to add the thumbnail and the title to the next and previous image.

Anybody figure this out?

You are probably looking for this:
http://www.zenphoto.org/documentation/functions/_template-functions.php.html#functiongetNextImageThumb
http://www.zenphoto.org/documentation/functions/_template-functions.php.html#functiongetPrevImageThumb

Please take a look at the documentation for more info about available functions.

Excellent! Thank you!