It seems that this time they are all in one page, but they are behind each other. If I change the size of background image in full screen mode, you can see this. For some reason the background image is number four in the queue of five. I would expect it to be first.
Ok that is a different problem, easily resolved. You are able to get the images on one page.
So let's add a step.
Starting from the point where you dragged your first smaller image on top of the background image, and you dont see it, go to the Full Page Editor screen.
See screen snaps.
See the small image outlined beneath,
See small image now on top,
You should see the selected small image's outline beneath the main image.
Right click on it, and select MOVE to FRONT.
Click DONE.
Fred