How to add lightbox effect to photos and images?
First, go to Directories -> [Your Directory] -> Content Types -> Listing -> Manage Displays -> Detailed and edit the display element that shows photos or images, for example the default “Photos” display element. Select “Gallery” for the “Field renderer” setting and save the display element. This tells Directories Pro to use the WordPress [gallery] shortcode to display photos and images.
Then install the Responsive Lightbox & Gallery plugin which turns the [gallery] shortcode into a nice gallery with lightbox effect. Configure the plugin to customize the look of the gallery displayed.