Incorrect locations in nav system

[rekoil]

Just got a Versa SL, loving it so far...except that the Nissan/Bosch nav system has a completely wrong location for my home address - it's off by over a half mile, which in a city winds up giving me completely wrong directions.

I know that I can store my actual home location in the system (but unsure of how you link this to the "Home" button), but what feedback/support is available from Nissan for reporting errors and getting them corrected in future maps? And how does one get updates - Would I need to get an updated SD card from the dealer or is this something that can be downloaded somehow?