In showflat.tmpl the height and width for edit.gif and reply.gif are still hardcoded.
You find them in line 160 and 168. simply remove these attributes.
You might want to add the size information for these images to imagesizes.php to get "good" code.
Open imagesizes.php and add at the bottom:
code:
// $size = GetImageSize ("{$config['imagepath']}/edit.gif");
// $images['edit'] = $size['3'];
$images['edit'] = "width="21" height="14"";
// $size = GetImageSize ("{$config['imagepath']}/reply.gif");
// $images['reply'] = $size['3'];
$images['reply'] = "width="27" height="14"";
Really nice feature i must say. Is there a reason, why the dynamic version is commented out by default?