It's irked me that I couldn't sync a google calendar from within NT Hidden Settings with a rooted Nook Tablet 8gb without incurring a fatal error signified by the red exclamation point denoting failure to sync.
To get the calendar working, an XDA developer's thread provided breadcrumbs, however, it turned out to be even easier than posited in this post .
(Note: This requires root, however, it requires little in the way of wizardry, XML editing, or fishing around in root folders.)
1. go to .
2. Download the acclaim_update.zip file to your PC or Mac
3. extract Calendar.apk and CalendarProvider.apk
4. copy these two files to your Nook (I copied them into the My Documents folder on my SD card)
5. Use a file manager to click on each of the apk's and install them using the Package Installer choice
6. Try to open each; each will give you an error.
7. go to home screen
8. power down with a long press of the on/off button
9. power on with a long press of the on/off button
10. Go into NT Hidden Settings, Accounts, select your account and put a check mark in Sync Calendars.
11. Wait a few seconds until it takes hold and the checkmark stays green (without a red exclamation point having appeared)
12. Voila. Your calendar is synced
13. go to the home screen, click on the App Drawer
14. Click on the Calendar app.
15. It loads
16. Test it by creating an event.