I also tried adding

function galleria_thumblinks(){
 echo '<script type="text/javascript">
$(document).ready(function() {
	Galleria.loadTheme('/galleria-themes/galleria.twelve.min.js');
	$("#gallery").galleria({
		width:720,
		height: 520,
	});
Galleria.ready(function() {
    this.$('thumblink').click();
});
</script>';
}
add_action('wp_head', 'galleria_thumblinks');

to my Thematic childtheme but can’t get rid of a syntax error expecting ',' or ';' seemingly focused on this.$('thumblink').click();