Hi Jim,
Thank you for your help. The advice you have provided concerns the manipulation of Cameos, but the Record Presentation function creates a video which does not have the full range of options which are available for Cameos.
As you can see in the image below. Record Presentation now makes an excessively ugly circular video, where it used to just record a 16:9 thumbnail in the bottom right corner (which could be moved, resized, cropped, etc.). Clicking on the round video does not give me the Camera Format option on the ribbon which is available if I use Cameos (such as manually inserting a cameo on every slide, which would be really time consuming). I tried tinkering with the Slide Master and adding a Cameo to every slide, but I'm not an expert, and the video ended up always at the back.
All i would like to do is just set it so that the Record Presentation leads to the old rectangular video, not this horrorshow.
PS - There's pretty good reasons for wanting the rectangle as it allows my hands to be seen in shot--useful for explaining things.
