Story size - Different sizes on the slides in the same course

Hi Helene, 

Thank you for sharing what you are experiencing and for providing that screenshot! Let's see if we can get you on the right path here. 😄

From the Story View, if you navigate to Design >> Then click on Story Size >> what are the current settings being used for your Story Size? Is the Lock Aspect Ratio box checked?

I do want to mention as well that the player feature does add some width and height to the published size. 

If you need our help to take a look at your file,  we're always more than happy to help!  You can share files in this thread here or you’re always welcome to share it privately with our Support Engineers. We'll let you know our findings and will delete it after having a closer look.