I can't answer the Q on how to configure GD as I avoid it (and other cloud solutions. My backups are Manually launched, to local storage while Calibre is shut down)
In General: Never allow ANY sync to be 2 way <=>, only allow a Mirror (copy) to be made. 2 way makes changes under the skirts that the Local DB might not get.
As to the FAQ
Click Calibre's
Help
The FAQ are a dynamic work.
You should visit frequently (I do wish they had 'change bars' ) to see updates.
The FAQ tend to cover Frequent discovered issues and solutions.
As I understand it: The GD one, was discovered years ago. Their 'versioning' method and Calibre {id} clash.