As far as checking whether you have the most current version of downloadable software, try this link... http://www.harley-davidson.com/cp/moar/en/software.asp
Many other GPS systems use a fairly standard format for map information, this is what I hope to determine when I get a chance later today to look at the disks... if so then perhaps some of the map information that is available via Internet web sites will be useable. (I have my doubts, afterall this is HD we're talking about).
As for accuracy, yeah my system has not been dead on when I've used it, and yeah it tried to take me three blocks out of my way to get to a road I could see from my driveway, but generally speaking it has gotten me close (except for a trip to Phoenix where it put me on the wrong end of a road - 1/2 mile or so). If your system is really out to lunch, try the calibration procedure before throwing in the towel.