I did a chat with support today, and after reviewing the things I had tried she suggested rebooting into recovery mode, and reinstalling the OS. That process will apparently update to the most recent version, so is a work-around for the stalling problem. I figured she would have heard an earful, but she hadn't yet encountered the problem, so I'm not sure why some of us had the issue but others apparently did not. Regardless, it took a while but it's now working and fully updated to 11.1. Hope that helps some of you.