I don't know where this fits into the new system, but I have a suggestion for a feature. My client didn't like the wide spacing of thumbnail pics in a detailed listing. He said put them closer together.

So I went into images.inc.php and added a css tag (class="IMG_TN") to the thumbnail image, line 1642 in the 2.5.8 release:

$display .= "<img src=\"$config[listings_view_images_path]/$thumb_file_name\" height=\"$thumb_displayheight\" width=\"$thumb_displaywidth\" alt=\"$caption\" class="IMG_TN"/></a>";

This way I can specify custom spacing for the images, and make them fit together under a 500px main picture:

a img.img_tn {
border: 1px solid black;
padding: 0px;
margin: 0px;