Downloaded MacOS Sierra Public Beta yesterday and after installation went to bed. W one up this morning and my iMac started up great, but so far the only app that is working is safari. NOTHING else is working, not even apple's built in apps. I did get the App Store and iTunes started but so far they are EXTREMELY slow. iTunes took 65 minutes to download a 55mb update to the CBS app for iOS. So far No CALENDAR, REMINDERS< NUMBERS, PAGES, MAIL, FANTASTICAL and it takes forever to for SYETEM PREFERENCES to start. Never had these issues on past betas and I have worked with public betas for MAVERICKS, YOSEMITE, and EL CAPITAIN in the past.