I have generated the log file as instructed above and sent it to the email indicated.

Note: The file, as generated, was named 2018-11-06T12_30_00.cblzip . I'm pretty sure
the correct naming should have been 2018-11-06T12_30_00cbl.zip . You might want to
investigate what caused cbb.exe to misname the file.

I submitted the ticket as you advised. What is the next step?

The file is on one of the HDDs on my PC; it is not on a network share. I currently have no network shares setup. The file shown is just an example. Seems any 'open' file doesn't get backed-up (with above noted error shown in the log). BTW when I tested Arq Cloud Backup it had no problem with 'files being used by another process'. I was hoping to used CBB instead of Arq because I prefer CBB's UI and restore functionality. But, before I purchase CBB I need to get this locked file issue resolved; if it can't be resolved then I'll probably revert to Arq.