Having issues trying to animate with JPEG images

Hello to Any and All

I am new to articulate, my third day on it and I am building an online training resource for an education provider.  I am trying to create a (stop frame) animation by building a succession of JPEG images (12 max) in a slide timeline. However although the images are in the timeline and all in sequence when I play or preview the slide there appears to be nothing, a blank screen as it were.

The people I am working for have commisioned an illustrator to create images in photoshop made of multiple layers.  I am saving each layer as a JPEG and keeping the size of each file to around 500mb so they are small images to be working with.  I assume this should be a relatively easy task to perform and is similar to what can be done in PowerePoint yet I am having absoulutely no luck...

What am I doing wrong and do you have any ideas or suggestions?!?

Thank you!!