[Plugin: NextGEN Gallery] Slideshow from thumbnails

hi i was wondering if there is a way to use thumbnails in slideshow instead of full-size images.

i used this code to get the slideshow into my template:

<script type="text/javascript" defer="defer">
<!--
//<![CDATA[
var sbsl1_1 = {
	params : {
		wmode : "opaque"},
	flashvars : {
		file : "<?php bloginfo('url'); ?>/wp-content/plugins/nextgen-gallery/xml/imagerotator.php",
		shownavigation : "false",
		showicons : "true",
		overstretch : "true",
		rotatetime : "3",
		backcolor : "0x000000",
		frontcolor : "0xFFFFFF",
		lightcolor : "0xCC0000",
		width : "93",
		height : "93"},
	attr : {
		styleclass : "slideshow-widget"},
	start : function() {
		swfobject.embedSWF("<?php bloginfo('url'); ?>/wp-content/uploads/imagerotator.swf", "sbsl1_1", "93", "93", "7.0.0", false, this.flashvars, this.params , this.attr );
	}
}
sbsl1_1.start();
//]]>
-->
</script>