I have the latest City Nav for Europe - 2013.1. I selected the entire map to load to my 4G SD card for my Zumo 550. It crunched away and eventually wrote the gmapsupp.img file to the card. It was just over 2.5G in size. Biggest img file I have ever seen created. Plugged the card into my Zumo and got nothing. I thought maybe the card was bad so I repeated it with another one. Same result. Obviously, the card works perfectly attached to my PC. I created a new map set with only 6 map segments - bout 50M total. Quickly created the card and installed it in the Zumo and it works perfectly. So I knew my new version Europe map program was good. So then I created a third map set with all of Europe again, but this time I left out enough map segments to get the size below 2G. It works perfectly. I checked my firmware. There was one newer version which I installed. The updated Zumo will still not recognize the full Europe map set that is greater than 2G. My friend who is travelling with me also got a copy of City Nav Europe and he has a Nuvi 660 that does exactly the same thing. Maps greater than 2G aren't recognized. He also checked and updated his firmware to the latest. So it isn't just my Zumo. BTW, I select the Tool icon, then Map, then Map Info to show the available maps. When it recognizes the map on the SD card, it shows in the list, When the file is over 2G, nothing but the original installed map is listed. There are no error messges, no warnings, no nothing. It is like you didn't plug in the card. Same sequence on the Nuvi and the same "no response, like you didn't do anything" result. The map sets were created in MapSource on a Win7 PC. Anyone ever run across this? Any solutions, other than carrying two SD cards for full coverage? Thanks.