Adding Slides & Images To Slideshow
To add more slides to a slideshow, click the existing slide, hover over the third option in the popup menu (Item Settings), and choose Clone Item.
To rearrange the order of slides in your slideshows, use the arrow keys that appear under the Item Settings submenu.
You can change your slideshow's behavior and design from the Slideshow Settings panel. You can find it by clicking the Section Settings menu item (the rectangle icon).