Thanks for response.
Can you explain a little more when you say "using the picture style and using animation on them without increasing the size of the individual slide"? Maybe give a little example?
Picture Style is one of the two default styles given as templates by CC with RCS . The background style is what your videos were about.
What I was hoping to do was to create a slideshow of photos with supporting text and for them always to remain the same size ( ignore responsive aspect for the moment). Not sure what I am trying to do is possible but I was trying to do something similar to when you are in a graphics editor with a main image you are able to lay over other images or text without physically altering the size ( length & width) of the image.
I have created a file which has the photos and some text describing the photo which is ok ( the slides are all the same size) but I would like to add some extra text to supplement individual slides hopefully without having to alter each photo where I add an extra element.