Replace this (line 167):

<a class="prettyPhoto<?php if ( $i == $img_count ) { echo ' last_attached_image'; } ?>" rel="gallery[<?php echo $post->ID; ?>]" title="<?php echo $img_title; ?>" href="<?php echo $image_src[0]; ?>"><img<?php if ( $i == $img_count && $cap == '') { echo ' class="no_bottom_margin"'; } ?> src="<?php echo $image['url']; ?>" width="<?php echo $image['width']; ?>" height="<?php echo $image['height']; ?>" alt="" /><?php echo $cap; ?></a>


with this:

<a style="position: relative;" class="<?php if ( $i == $img_count ) { echo 'last_attached_image'; } ?>" title="<?php echo $img_title; ?>" href="<?php the_permalink(); ?>?ss=true"><img<?php if ( $i == $img_count && $cap == '') { echo ' class="no_bottom_margin"'; } ?> src="<?php echo $image['url']; ?>" width="<?php echo $image['width']; ?>" height="<?php echo $image['height']; ?>" alt="" style="margin-right: 0; margin-bottom: 15px; display: inline;" /><?php echo $cap; ?></a>