In 2017 there are two configuration files.
General settings in “config.dict”.
Theme setting in “customer_theme.properties” assuming you have created a custom theme.
With Moneydance shut down you can rename either of these file and on restart “config.dict” will be recreated with default setting and “customer_theme.properties” if you set a custom theme.
You can delete the new files at any time and rename the renamed files back to there original names to get back your old settings.
If you have any trouble finding your Home Library folder, open Finder and select Go>Go to Folder> and type in:
This should pull up your local Library folder.
Moneydance should be automatically saving any changes to your configuration file. Are you trying to move these to a new system? If so, they should be used with the same version of Moneydance, and exchanged for the existing config.dict file only when the program is not running.