Enter an optional URL if you want the Gallery to include a link back to your regular web site. You can also enter an email address if you want your web gallery to include a "contact" link.
The option "Image View Size" defines the size of the detail image which opens when a visitor clicks on a thumbnail picture in a gallery.
With the option "Rollover Effects" selected, thumbnail images will change appearance when a visitor moves their mouse pointer across them. This will provide good visual feedback but somewhat increases the size of the final HTML code and its components. When this option is turned off the page will load faster.