how do I transfer an OSM map to my device?

I have a GPSmap 62s and have just downloaded an autoroutable OSM map from a website but can't figure out how to get it on my device. I have been able to load the map into BaseCamp but not the device itself. The website instructions are no help. It tells me to download the gpsmapsupp.zip file from the site, unzip from it the .img file and send that to my SD card. The only problem is that the map file I downloaded from the site was an .exe file, not a zip file, and the .exe file unpacks into many .img files, none of which are called gpsmapsupp.img. I realize that asking someone at the website might be a better way of getting help than this forum, but I need to get this done by early tomorrow morning and was hoping for a faster response here. Afterall, if I can get the map loaded into BaseCamp then surely someone here should be able to guide me from there.

Thank you.

 

Ugh, nevermind. When I opened BaseCamp I immediately went to the maps drop-down menu and the Install option was greyed out. But after posting my question I went back and the Install option was available. I guess it takes a minute or two for BaseCamp to detect the SD card? Anyways I've installed it.