Dynamic Page Loader Conflict

Now that your site is a little further along I can see what's going on a little better. It looks to me like the jQuery is not being called again when the gallery page is "loaded" since the page has technically already been loaded once. What you need to do is add something like this to your page:

$(document).ready(function(){
  $("#gallery").click(function(){
    Galleria.loadTheme('galleria.classic.min.js');

    // Initialize Galleria
    $('#galleria').load(function(){
        $('#galleria').galleria();
    });
  });
});

I just tried that on your site using the chrome console and it worked. One thing that might snag you is that you will need to wait for $("#gallery") to be ready before you should reinitialize galleria. It worked with the console, but it may not work if you have it within your page.

Another note, you should add the height element to your galleria call. It tends to be a stickler for that:

$('#galleria').galleria({
    width:500,
    height:500
});