I wanted to have the same solution to this, for a client to display their menu on the website, but not displaying every thumbnail. I kind of did what Klynam did in this post:
But using my wonderfull CSS editor Stylizer, I quickly found the right CSS tag, and did a display:none on the image list/thumbnails.
First, I used Chrome to check the code for the link to the first full image in the list. And, I also check to see the REL tag for that link. It was rel="lightbox[set_1]".
Then in WordPress, I can use any image in my page/post as a link for opening my now CSS hidden image gallery in Lightbox mode.
I added an image to the post in the usual way, and as Link URL, I pasted the link to the first full image from the gallery. In Advanced Settings, I just pasted the rel="lightbox[set_1]" into the Link Rel field and inserted the image into the post. Now it works as a link, and are only displaying the images thats added to the gallery.
I think it works nice :)