Here is what I have found out so far. Non NAV Apim units don't have a NAV license which appears to be a hangup. I can enable NAV ad load NAV software into a non NAV unit but it still will not function as a NAV unit. I can downgrade NAV units to do "Information" only and bring it back to NAV as it has a NAV license. I even went so far as to take a non NAV unit, put it in my car and do a legitatemate APIM replacement procedure through PTS/IDS and it still doesn't add the NAV license.
So right now what can work is taking a used APIM that has NAV and custom configure it for your vehicle. Much like the 4D Tech people are doing on ebay right now for $1200. I suspect they have figured out how to add the NAV license though.
If anyone is truely a die hard and wants to add NAV to your 13+ Taurus I can probably do so for around $500 which would entail getting a used APIM and configuring it for your vehicle.