To add an image gallery to any page, follow these simple steps:
1. Create or edit the page you'd like to add an image gallery to
2. Click on the (+) symbol to the left of the Main body content area
3. On the popup that appears, choose "Image gallery" as the element type
4. On the next screen you can choose existing images from your library, choose stock photography, or upload from your computer. Once you have the images loaded into the library, you can use the Shift key to select multiple (the ones with the blue outline are selected)
5. Once the images have been inserted in to the content area, you can reorder them using the handles to the left of each image, and/or add captions. If you need to add additional images you can do so using the "Add image" button.
5. Save your content, and you have a gallery!
Note that the first image will be used for any teaser display of that content, by default.