Carl,
For Windows, the documenttion describes the following folders.
C:\GAMADV-XTD3 - The executable folder
* This folder should be on your system path
C:\GamConfig - The configuration folder; gam.cfg, client_secrets.json, oauth2service.json, oauth2.txt, gamcache, ....
* This folder is referenced by the system environment variable GAMCFGDIR
* This folder is referenced in gam.cfg as config_dir
* The cache folder is referenced in gam.cfg as cache_dir
* This what you have in C:\Users\sundermannc\.gam
C:\GamWork - The working folder, scripts, CSV files, log files, notes
* This folder is referenced in gam.cfg as drive_dir
Here is a one main folder alternative
C:\GAM
C:\GAM\Binary - The executable folder
* This folder should be on your system path
C:\GAM\Config - The configutation folder
* This folder is referenced by the system environment variable GAMCFGDIR
* This folder is referenced in gam.cfg as config_dir
C:\GAM\Cache - The cache folder
* This folder is referenced in gam.cfg as cache_dir
C:\GAM\Work - The working folde
* This folder is referenced in gam.cfg as drive_dir
Copy the contents C:\Users\sundermannc\.gam as deired, update the references in gam.cfg