I wanted to mention that the process for transferring the file outlined in this post worked extremely well.  The clarification point, provided to me by a young lady on QB chat support (thank you Alexis!) was to download and install the trial version of QB 2021 for the Mac, use this as specified to import and export the data, and then pull in the data to my Windows program.  All data from the last run P&L and Balance Sheet match exactly.

Thank you.