[Windows Mobile Development and Hacking General] TheSt33v:
I thought it would be nice to distill all of the information provided in this thread: http://xdaforums.com/showthread.php?t=3368080 into an easy to follow guide. This method was originally described here: https://www.drive2.ru/l/10018006/

Before you proceed, please understand the following:

I am very new to modifications like this and I'm not very knowledgeable. If you mess something up, I probably won't be able to help you.

The following guide is the steps that I took to get this working on my 2012 Ford Focus. I'm not aware of any car model-specific issues, but that doesn't mean that there aren't any.

This guide is for North American cars. If you live in a different region this will still probably work, but you will need to use the MyFord Touch system software files that correspond to your region.

What you will need:

Forscan (I used version 2.3.4 beta) from here: http://forscan.org/

An extended license for Forscan. Follow the instructions to get that here: http://forscan.org/forum/viewtopic.php?f=5&t=836

An ELM327 OBD2 adapter that is compatible with Forscan. I used this one: http://www.totalcardiagnostics.com/shop/elm327-obd2-scantool

This png file: https://yadi.sk/d/i-JGQR8ZwLrLM

A USB flash drive

MyFord Touch system software version 3.8 (also known as SYNCGen2_3.08.15128.EA.10_PRODUCT). This is the latest version as of this writing. If you aren't on it, you can get the North American update from here: http://ivsu.binaries.ford.com/swparts/Gen2v38build15128updatepackageNARev2.zip. Install it if you don't already have it.

An SD card that contains the navigation maps. The latest version for North America is A8. The latest version for Europe is F6. You can use older versions if you like. Find them on eBay or somewhere similar.

These nav-related files: https://mega.nz/#!DVwQXYQD!BnXXpR9XuhE7ZQPIjM7ODM0SYepJCSawR3q1Ps2XT_s.

Got everything? Let's get started:

Plug (or pair, if you're using a Bluetooth adapter) your OBD2 interface into the OBD2 port on your car.

Put your key in the car and turn it to the On position (the first click after off. Do not put it in accessory mode, which is the second click).

Start up Forscan. You should be on the Vehicle and Interface Information screen (the icon looks like a car with an "i" in a yellow circle on top of it).

Click on the icon that looks like two power cables plugged in to each other to connect to your car. You'll see some information start to populate the log. Wait until it is completely finished.

Forscan might show you a menu with different vehicle options to pick. Pick yours from the list. In my case, it asked if my Focus was 2012 or 2013.

If at any time Forscan asks if you want to save something so you can back it up later, say yes.

Click on the icon that looks like a microchip and under the Configuration and Programming tab, select APIM and press the play icon.

You'll see a lot of fields that are labeled with numbers that start with 7D0. Click the disk icon at the bottom of the screen to save a copy of these original values.

Find 7D0-01-02 and change the first two numbers in the first field from 00 to 04. Click Write to save the change.

You'll see a warning message about the checksum being bad. Click yes to ignore it and continue with the change.

Go back to the Vehicle and Interface Information screen (the icon looks like a car with an "i" in a yellow circle on top of it) and click the unplugged power cables icon to disconnect your computer from the car. You can remove the OBD2 interface now if you like.

Put the png file that you downloaded earlier on to a USB flash drive and plug it into the USB port in your car.

In MyFord Touch, go to settings -> display, and find the setting for changing the wallpaper (I forget exactly what it's called).

Click on Add, and select your USB drive. Highlight the png file, and in the preview box, you should see a blue button that says "enable nav" or something like that. Press it, and you should see "nav enabled" appear above it.

Extract the nav-related files to your USB flash drive and plug it in to your car. It will install some things (be patient, let it finish) and when it's done, you should see an "i" icon at the bottom of your home screen.

Insert your navigation SD card into your car's SD card slot, and you should be good to go.

Hopefully you now have access to a navigation system that is every bit as sub-par but adequate as the rest of the MyFord Touch system. Congrats!

UPDATE: Someone just told me that their car wouldn't read their map card until they installed the package that I labeled optional, so it might be worth a shot if you didn't use it and you're having issues. Again, that package is specific to North America, so if you need a different region, you'll have to find it yourself unless some helpful reader wants to provide a link, and I'll post it here.