Hi tester_76
have a look in post #1
If you own a thai firmware you can choose the proper jcv file . And of course if your device is compatible with Junction Views .
Scrolling the thread you'll find which differences between each file.....one for bangkok zone (if I understood well) , one for a zone I don't remember...it's just a kind of "training" that you can do with your device......and learn a little step more.
Try a trip in demo mode. So you can confirm to all Thai users wich is useful for their zone.
Bye,Umbe