Not sure if this is resolved yet, but I figured I post this for others. The solution in the oiko post will work with responsive lightbox if you adjust the $priority variable to something higher than 1000.
add_filter('wp_get_attachment_link', 'oikos_get_attachment_link_filter', 2000, 4);
I walked through the code a bit and discovered that in add_gallery_lightbox_selector, the link is overwritten. Since the oiko solution ran prior to add_gallery_lightbox_selector, the links always reset to the link for the full image. Or at least that is how I interpreted it. ??
Hope this helps others.
