This is an early beta version of focus mask plugin for Lightroom 4.x and 5.x. After installation, you can open the plugin from File / Plug-in Extras / Focus Mask menu item. The plugin opens with either single image, or several, depending on your current selection. In single image mode, the photo is shown in larger size, and in multiple images, the view can be scrolled. Currently, the amount of images is restricted to 32.