Thanks for all the help and links on this guys, especially the Ross tech link.
I looked into the gateway upgrade today, i can upgrade the software through the VW system
I searched the TPI number ( as mentioned on the ross tech site) on the VW system today and now have a action code to update the software instead of buying a new unit. The TPI is recommended for the fitting of a VW towbar , seems this can cause a battery drain as well.
Will give it a bash then test the car for battery drain after fitting the 510.