Hello everyone. I am needing help trying to convert shapefiles to be able to use on a Garmin Nuvi 255w. The Fire Dept didnt ask us or anyone else for that matter, what GPS unit they should order to be able to manipulate the maps within the unit. So, they ordered the garmin and now want us to be able to add layers within the GPS units. Does anyone have any info on how to possibly achieve this? I called Garmin and the only use they were was to tell me the maps supplied are in .img format.