it should be the same as in any other version. basicaly it should be the mapdrawer and poicats nfs and the map you want to be navigated to. but the other nfs files are not too big, so to be sure copy them as well, and the phoneme and landmarks nfs, which are larger the the other nfs. those are for other features, like bt phoning and 3D buildings, which this navi probably does not support.
Thanks usiRev. Decided to use expansion micro sdcard and put maps there instead of trying to replace 2009 maps on device. Downloaded 2001 q3 maps and nfs files.Put in NAVIGON\map folder in root of sdcard (formatted fat32).
Selected "Europe Version Q3 2011" map on device via options\map display\(page 2)\Countries in(list icon).
Now to update NAVIGON software!