To open a picture, click on the small preview icon. The picture will open in a new window.
To save a picture, open it, and then click on the little download button in the bottom left corner.

To begin the slideshow, click on a picture (the one you want to begin the slideshow with), and in the new window, select "Start Slideshow" option; which is located at the upper left corner. To stop the slideshow, simply click on "Pause Slideshow" (same place as the start option: the upper left corner).

To browse through the pictures, move the mouse towards the bottom of the image. A linear list of the images will appear. Select an image you want to view.

To move to the next/previous picture, simply move the mouse towards the left/right side of the image and click the ">>" or "<<" signs; or you can click on "Next" or "Previous" text at the bottom of the window.

To close the gallery window, click on the little X sign at the top right side.