I wanted to do a reorganisation yesterday so I created groups and attempted to move sections into them. Both drag-and-drop and context menu worked, but next time it synchronised with the server I ended up with the original sections plus the ones in the group. I then had to go through and manually delete the external sections and hope I wasn't losing anything.
I was using the Mac App Store version purchased on Saturday with iCloud storage.
The Question? Is this a known bug?