I bought a Zumo 550 off the flea market last summer , was thinking about updating maps,never have done it before and getting ready to go on a 3k ride in about 2wks.Well I started to look thru the stuff I got with it and their is a dvd with it and it says on it City Navigator NT set up and map data.I was wondering is this the software I will have to down load before I can download the maps.I didn't get a owners manual with it and I'm not the smartest with the computer.And on the sleeve it is in it says the software came with 25 character unlock code that I will need,where can you find that. thanks for any help I can get.