Same deal as far as I know, you should be able to buy a CD with the updated maps from the dealership and you can either install them yourself of pay the dealership to do it for you. There was talk of an update early this year so it should hopefully be out by now, must check myself.
Have you tried doing it the same way as the Gen 2 thread describes?
I'd try it myself but I seem to have unloaded all the cars with mygigs in them. Back when I had them I always was on the lookout for updating maps (other than by getting screwed over at the dealer) and even on mofv.com, which had everything to do with mygigs never had any info on that. Was always only ever firmware and Gracenote.
Thinking about this.... as far as I know there's only 2 map people. Whereis and Navteq. Now WhereIs=Telstra=Sensis. Garmin I believe get their maps from Navteq and then Chrysler royally screws everyone over sometime later when the maps are almost redundant by the time they get around to it. So, if it's Garmin then maybe it's updateable the same way as the Gen2. If it's a Sensis map then I note there is a Sensis image 2015.10 available from the same place as the Gen2 ppl get the Garmin ones. Might be something to look at. As I say, can't help in doing it, sorry.
Edit: Tell a lie, the Sensis image file is 2014.40
The first gen MyGig runs Navteq maps, but you can only obtain them through the dealership and not direct from Navteq. The information I posted in the other thread was actually in relation to the first gen maps and if I recall correctly it was $130 for the CD and probably around the same again to have them installed at the dealeship, but you can do this yourself. I think Chrysler only does an update every couple of years and my 2010 model has maps on it that must be around 2006-2007 vintage.
The trouble with CJD Australia owners is no-one with a disk makes an image of it. At least with the WhereIs maps I was always able to find a copy of it for an aftermarket unit my missus had in her Toyota.