Gradually more collections will be added. Not all my images or Albums have been made into collections.
When you open an Album there are three alternative methods of viewing the Album displayed at the top right:
As a Slideshow - icon is like a computer screen with a play button. You can pause/continue the Sldeshow using the space bar. Or click or touch the pause/play button at the centre of the image.
As thumbnails - icon is like a brick wall.
In a larger size - icon is like a coloured square.