1) full backup your TT (better use usb cable + windows explorer copy / paste)
2) check and get the map you want (check if it works with your Navcore version in the chart)
3) delete the old map folder from your TT
4) uncompress the new map to a simple name folder (something like America_North or just America - keep similar name as older map was)
5) get (it's avaiable in the tweak / open forum section) FastActivate Premium uncompress and place the exe file in the root of your TT
6) double click on FastActivate Premium and do as follow:
a) update meta.txt
b) patch maps / voices / speedcam....
c) patch ttsystem files
d) patch tt home
7) turn TT off and discon from pc
8) turn TT on and test
9) you've yourself a new map to play with lol
NOTE: if you have good POI's and favs that you want to keep, after you have done all that above, go to your old map saved folder and get a file called "mapsettings.cfg". Place it into your new map folder and overwrite the existing one.
Now you are done