I installed r 8.2.1509 over r7 database and it all came up fine. Deleted old r7 first.
IMAP/SMPT works great and Calendar and contacts were fully populated. Did not realize till later that caldav/cardav won’t sync.
Deleted caldav/cardav but now can’t create new account. Authorization fails when I enter my iCloud login ID. Says need apps specific p/w but I have one and have re-entered it 5 times. Using same one as on Win10 mail app which came up immediately on first try, also same apple p/w that worked fine with r7.xx.xx earlier. Mail with IMAP/SMTP is fine.
Tried following directions at this link. www://emclient.com/em-with-icloud
does not work. Ran an iCloud log but log files only show the IMAP email addr, not the apple ID email.