Form Blank Submit Button is Empty

I’ve installed the plugin and specified .content for the form results. I’ve placed <?php echo do_shortcode("[AjaxWPQSF id={form id}]"); ?> in my template and the form’s border and submit button show but nothing else. There is also no text in the submit button.

Can be viewed here

Any ideas?

http://wordpress.org/plugins/ajax-wp-query-search-filter/