Is there any way to get the new calendar widget or current day widget to work with outlook rather then iCal?
it uses the Apple EventKit framework, so it will support any calendar app that works with that. Unfortunately I have no idea whether Outlook is able to sync with that api... probably not ;-(
My company locks down access to exchange, so we can only access email / calendar via the Outlook app. But in theory, if you are able to System Preferences, and Internet accounts and add the exchange server there and enable Calendar. Your Outlook calendar will download to Apple Calendar and you may be able to use it with BTT. But if your company uses something such as Conditional Access for the exchange server, then would not work. Would be great if it did.