If your watermarks aren't showing up on your images you can check this list of common reasons that may be happening.
* The Display Watermarks option has been unchecked for your gallery.
To remedy that click on Photos > Galleries then click on the name of your gallery. Scroll down to the Gallery Options section and check the box for Display Watermarks and click Save.
* The Watermark Placement box(es) haven't been checked or the Watermark Opacity is set too low.
To remedy that head click on Photos » Preferences, scroll down to the Photo Display section. Choose either the small or large watermark option.
Small - Select one or more positions to display your watermark image. If no positions are selected, no watermark will be displayed.
Large - A single large copy of your watermark image will be displayed. You must upload a fairly large watermark file to take full advantage of this option.
Set the Watermark Opacity: 0 = invisible, 100 = fully opaque. Click Save.