Display Child Pages in Custom Menu

I’m fixing a custom theme a friend paid to have developed for them. The original developer used a weird plugin to deal with the menu, rather then registering a custom menu and then using the Appearance>Menus option already built in.

So, I’ve registered a custom menu, created and saved a custom menu, but cannot get the child pages to drop down from the parent pages in the menu. Yes, I have “indented” the child pages in the custom menu set up.

This is the code I’m using right now

<div id="nav">

    <ul>

<!-- <li><a href="<?php echo get_option('home'); ?>">Home</a></li> -->

           <?php wp_nav_menu( array( 'container_class' => 'nav', 'theme_location' => 'primary', 'depth' => 1, 'fallback_cb' => 'wp_page_menu') ); ?>

    </ul>

    </div> <!-- END NAV DIV -->

Am I missing something? I did add navigation java script, within the functions.php file and in a js folder. No child pages will appear!