Hi, the answers to your question are;
1 - Yes, via onedrive.com
2 - Yes, I have a Windows virtual machine and OneDrive Sync's without issue.
3 - Yes/correct
4 - Yes, they have the same issue.
5 - No, I have the same issue.
I followed your instruction to re-install the client and I get the same issue after the re-install.
I have also attached the OneDrive log files (~/Library/Logs) from the re-install test for your reference.
(Please visit the site to view this file)