I wish to update to the latest UK and Europe maps on my Nuvi 660 and have found City Navigator 2012.20 on other links in the forum but need to know if a new basemap (gmapbmap.img) should be installed at the same time and which is the latest version and download link? Mine is the original supplied with file size 6.44 MB (6,762,496 bytes) but don't know how to find which version it is so any info would be useful.