Pre-Selector is minimal by design, maintaining MacOS look and feel, it layers the app in windows.
Drag and drop your image folder directly into Pre-Selector or click the folder icon. For practical purposes, some cameras create a pair of images consisting of a RAW file and a JPEG file, they're the same with different format. Don't worry about that, Pre-Selector associate both files into one.
You can also go to File > Import Images or pressing ⇧ + ⌘ + I
Rating and Selecting Images
To select images for compressing, click the upper-right checkbox next to the image. You can also select and rate from the Preview Window.
To rate use the stars located at the bottom. Later, if you want, you can filter images by number of stars they have.
Also, you can select and deselect all images by cliking one of these options on the toolbar menu. Note that, Erabo will respect any applied filter.
Preview mode let you view an image up close. You can also rate and select on this window.
To enter Preview Mode just double click the image or single click and hit the space bar on the keyboard.
Filtering comes handy if you have many images on a single project. After you rate your images, you can filter them by the numbers of stars you gave them, "All", and "Not Rated".