FYI: Found the answer for my GUID password question:
Scripts may store credential tokens as convenient for the script author. Credential tokens are not related to the password in its original or encrypted form within NetSuite. These tokens are unique identifiers which allow a script to refer to an encrypted secret securely stored within the SuiteCloud platform. Automatic password expiration is not currently provided, nor is it possible to view an inventory of saved credentials in the user interface.