Backup on your pc old files before making any change.
The gmapsupp.img must be placed in a folder named Garmin in mmc
The other files(Lane Assist file,3d building and time zones) should be placed in the Garmin folder, which is in the unit (not on the memory card!). But do not forget, that they works only with the Garmin Nuvi 7x5 series and the Garmin zūmo 660 GPS navigators
The old files must be replaced