Hi Martyn,
The chart is a summary of the commercial and reasonably uptodate map packages available for each platform. I've spent quite a bit of time scearching for these packages on the web sites of a number of the Australian mapping vendors.
I am aware of the Festy maps but these are based on map imagery from 2005/2006 which is starting to get fairly old. Even in the brief look I had at the Nadgee sheet, there are some minor problems with the mapping. On this particular sheet there is a strip of mapping that is duplicated twice for example.
The Memory-Map topo imagery is a 2012 release of updated mapping produced by NSW department of lands. If you can let me know of an official release of the NSW topo mapping that has been published in the last 3-4 years in Ozi Explorer format please let me know and I will update my chart accordingly.
Cheers
Paul

