The 'Link & Lightbox' area allows you to specify a link or lightbox for both the slide image and the thumbnail image. All you have to do is specify the URL of the link in the 'Path' field. If you want the link to be a lightbox, you will need to check the 'Lightbox' option.
If you want the links to be opened in a lightbox, please note that you can load images, YouTube, Vimeo or HTML5 videos, web pages, or inline HTML content.
When you open a Vimeo or YouTube video, all you have to do is specify the URL of the YouTube/Vimeo page; if you want to set a certain size for the video, you can do this by passing a width and a height to the URL of the video: http://www.youtube.com/watch?v=JVuUwvUUPro?width=700&height=400.
You can open HTML5 videos by specifying the path to a MP4 video. Please note that HTML5 videos also need an OGG version of the same file for playback in Firefox, so you will need to have an .ogv version of the video in the same location as the mp4 file. These files also need to have the same name.
When you open a web page, you need to pass 'iframe=true' to the URL of the page, and you can also pass a width and a height: http://yahoo.com?iframe=true&width=700&height=400.
For loading inline HTML content, all you have to do is specify the ID attribute of the content in the 'Path' field.
If you set a lightbox for the slide, the image's 'alt' text will be used as a title for the lightbox window and the link's 'title' text as a description.