Thank you very much for the quick reply.
Another question if you don't mind:
Do jcv and Gmap3d.img files have to be the same version as the main map file? ie, if using 2011.30 gmappsupp.img, the the corresponding jcv and 3d files must be 2011.30, not .20 or .40.
I ask this because when using the 2011.30 AusNZ map, erratic drift occured in my machine. There is no problem using 2011.20 map (Don't know why, still trying to resolve it).
Can I use 2011.20 map with 2011.30 jcv and 3d.img?