Newbie here. The internet contains a lot of information about how to decompose an .IMG file for use on a PC, but I want to do the opposite. On my PC, I have a mapset stored as a set of files with extension .GMP, each in its own subfolder. My device (Nuvi 200) requires a mapset to be stored as a single file named gmapsupp.img. I want to create an IMG file from the GMP files. Can anyone here tell me how to do that?