@Malyse Thank you! I have now installed Windows 10 (OMG), and so I can work with Astropad and Windows Powerpoint. If I need to do something to set up Windows Ink, I am clueless about it.
I can see the dotted bounding box representing Astropad's share of the Powerpoint slide, but there is no inking happening. I was hoping that the drawing fuSo nction might come into play -- the controls look similar to the hand-drawing functions in the Mac Powerpoint on the iPad. But alas no leverage there.
So I believe the piece I need to learn is how to activate Ink on Windows. I will try looking at MS Help.