IT IS SAFEST TO *NOT* selectively copy only certain parts of your data between sites/databases.
The intended proper upgrade procedure takes your ENTIRE database at one time. Yes, that may mean you'll have to re-do some admin-side settings changes or addons after redoing your upgrade on your live site. THAT IS THE SAFEST WAY. Any other approach should only be done if you have SOLID database skills and solid understanding of the ZC database architecture.