eNews Theme: Replace Post Thumbnail

In single.php replace:

$thumbnail = get_thumbnail($width,$height,$classtext,$titletext,$titletext);
$thumb = $thumbnail["thumb"];
if($thumb <> '') { ?>
    <?php print_thumbnail($thumb, $thumbnail["use_timthumb"], $titletext, $width, $height, $classtext); ?>

with

<!-- Modification 3/6/14 to display thumbnail from custom field -->
		  $myThumb = get_post_meta($post->ID, 'Thumbnail', true);
		  if($myThumb <> '') { ?>
		  	<img src="<?php print($myThumb) ?>" class='thumbnail alignleft'  alt='GitHub Developer Program Emphasizes Integrations' width='172' height='172' /> 
			
		 <?php } else { 
		  	$thumbnail = get_thumbnail($width,$height,$classtext,$titletext,$titletext);
		  	$thumb = $thumbnail["thumb"];
		  	if($thumb <> '') { ?>
			    <?php print_thumbnail($thumb, $thumbnail["use_timthumb"], $titletext, $width, $height, $classtext); ?>
		<?php }; ?> 
<!-- End Modification -->