Just over from the Graybox issue on the s9y forums. I agree with you, lightbox plus is better for your need. I have got graybox to work on my site.
I use it for the comments popups... but may end up using another of the lightboxes.
I'll soon be getting around to using your DTR plugin.
I looked quickly. I was thinking it would be nice to be able to group images and make them a gallery using this technique, but I haven't got to that yet... Maybe something as simple as adding a flag in the entry that would make all the images in one entry into a gallery...?