I restored my iPod-touch 4 data to my new iPod-touch 5, and the calendar was looking good, until I realize it was not syncing.
I tried deleting my Google Account and creating again, twice, with no success (now the calendars and events are not even showing in the app).
Also, I tried both Google account and CalDAV account, but none of them are even downloading my calendars.
I use two-step authentication, and I'm using app generated passwords each time I try to add a new account to sync.
The GMail sync is working properly, only the Calendar have some problem.
Is there anything more I can try? Or should I restore and keep my iOS 6?
(By the way, the Reminders are not syncing with iCloud, and Safari is crashing as soon as it opens, even after a few restarts of the iOS. But the calendar is the big problem right now)