Thanks for the response.

Yesterday I spent probably 45 minutes on the phone with a QB representative. I gave him access to my screen. He did all the things I’d already tried (verify data, compact data) and then concluded that the case needed to be escalated. He kept cautioning me that my data was corrupted. 

His solution was for me to pay $350 to have my data file fixed, I’d also get a 60 day warranty. 

From what I’ve done (see my original post), I’m pretty well convinced that my data file is not a problem, and that there is an incompatibility with my version of QB and my Mac operating system. I am hoping that someone can verify this conclusion.