Google Slides file doesn't appear in Desktop>>App WIndow

I opened the oogle Drive. Selected and opened a Google SLides file in a new window. I have followed the instructions for creating a PIP preset to include a cam image in small box and Google Slide presentation in the larger frame. Iset up the cam so my image appears in it live. Then I click on the larger frame. Scroll down to desktop and over to App window per isntructions. All that appears is WIndows App Server Window and “Many Cam Manycam” which produces an infinite iterations of the screen.

Why doesn’t Manycam show the presentation as an option to open?

@BGR Try to allow Screen Recording in macOS: