Select the photo in the app to edit its name and to choose wether you want the widget to show it or not (and its color).
Import the picture or pictures you want to show on the home screen as a widget to the app.
Create a widget, edit it and choose the photo you imported.
If the picture is wide or tall, be sure to set its center to make sure the important part is displayed on any sized widget.
Unlock the app to also creat multi photo widgets that display each picture for your chosen amount of time or at specific times in the order you want.
NOTE: If you find a bug, please click on the support link and send me a message with the details.
Create the widget as before and select if by its name when editing it.
Choose the type: Mosaic and Free Mosaic show multiple pictures in the widget.
Be sure to edit the composition if you choose Free Mosaic to place the pictures, scale and rotate them to your liking.
You can also add a custom link to your photos so once pressed it will be opened.
I've included an easy way to link to your own shortcuts by name.