@CATYMAG, If i have done everything according to instructions, it seems that there may still be some issue, it may even be it still is not working. When select wakling on my 3790 go into trip planner press create new trip,select location (which is not in melbourne its city about 40miles away, select home, then next screen will show 1.home, But this is where the option of "next" is still hidden, this tells me that xplorer is not working. ( xplorer is enabled along with all AU maps that are pre-loaded on 3790)
I have set walking 1km as the Bus stop is near and that should get me into the rail station then into melbourne and final destination.
If you think i have followed instructions on how to unlock as you have read and you seem to be satisfied i have, then there must be something im missing.
I will later try and unlock the Sydney map and see what happens. I am aware that i can keep same map/unl name and place other xplorer maps into "map" folder also, as i have NY and Paris there.
Let you know how it goes, if you have any ideas i appretiate your input.
cheers