Issues with Screen Recordings

I've used the screen recording very (very, very) successfully in the past, but right now I'm having difficulty.

1. Storyline file with a screen capture suddenly becomes "corrupt." Once this happens I can't open it or earlier versions. I've seen 2 messages: one the file is corrupt, and, two, the file is using other resources (it is not, nothing else is opened).
2. A screen recording inserted in a file using View Mode step-by-step slides is not coming into the timeline, although it appears in the Screen recording list. If you insert it as a straight video to check, it doesn't come in although it shows in the list of the screen recordings.

I began closing and opening Storyline, then did restarts, then uninstalled and re-installed Storyline. I've also run a virus check, no issues. I'm using Windows 10, V 1903. 

Thank you!