Automatic Youtube Video Posts Plugin Warning: Illegal offset type

Warning: Illegal offset type in /wp-content/plugins/automatic-youtube-video-posts/core/video.php on line 72

I’m using the most recent version of WP and a child 2010 theme. It was all working fine (no error) until I updated WP and the plugin.

This is how I’m calling in the thumbnails:

<?php the_post_thumbnail(array(100,100), array('class' => 'alignleft post_thumbnail'));?>
              <?php the_excerpt() ?>

And this is in the functions.php file

// This theme uses post thumbnails
	add_theme_support( 'post-thumbnails' );

and

/* this is for thumbnails*/
if ( ! function_exists( 'twentyten_posted_in' ) ) :

function get_post_thumbnail() {
 $files = get_children('post_parent='.get_the_ID().'&post_type=attachment&post_mime_type=image');
 if($files) :
 $keys = array_reverse(array_keys($files));
 $j=0;
 $num = $keys[$j];
 $image=wp_get_attachment_image($num, 'large', false);
 $imagepieces = explode('"', $image);
 $imagepath = $imagepieces[1];
 $thumb=wp_get_attachment_thumb_url($num);
 print $thumb;
 else:
 print "<?php bloginfo('stylesheet_url'); ?>/images/post-thumb.png";
 endif;
 }
//

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