The header file for you theme.
It should be in folder wp-content->themes->’the theme your using’. And be named header.php
Hi, had the same problem and did a site specific fix for it.
The problem seems to be that the plugin loads the javascipt files in the wrong order or the wrong way.
What i did to fix it was link to the scripts directly in the header, below the header tag.
The tags should look like this:
<script type="text/javascript" src="http://www.mydomain.com/wp-content/plugins/nextgen-gallery/js/jquery.cycle.all.js?ver=3.0.3"></script>
<script type="text/javascript" src="http://www.mydomain.com/wp-content/plugins/nextgen-gallery/js/ngg.slideshow.js?ver=3.0.3"></script>
Put that below you <?php wp_head(); ?> tag in the header for your theme, with “mydomain.com” replaced with your domain-name, and it should work.