Keven, I tried this, but even after closing and restarting MD several
times, I'm having to enter the Master PS.
I think that with the newest version of MD, files are automatically
encrypted and it's not set up to use the master password.
You are correct; the Master Password must be entered each time that you access your data file. Creating a Master Password allows Moneydance to then remember online passwords. (when the appropriate checkbox is ticked)
It is my understanding that creating a Master Password takes the place of the default encryption key. The Master Password creates an additional layer of security for access to your account information. Let's say, in the event of a lost or stolen laptop.