Kind of bike related as this is for use on my bike.
I’ve bought Garmin and am trying to install OSM on it.
I downloaded a map from http://talkytoaster.co.uk/maps/

renamed it gmapsupp.img created a file on the SD card called Garmin, place the img file in this folder.

The GarminDevice.xml file says

<Name>SupplementalMaps</Name><File><Specification><Identifier>IMG</Identifier></Specification><Location><Path>Garmin</Path><BaseName>gmapsupp</BaseName><FileExtension>img</FileExtension></Location>

Which to me tells me I am putting it in the correct place.

When I am in map mode and I go setup map the options I get are only the base maps.

What am I doing wrong!!

What model Garmin?
Did you unzip the file before renaming it?
Do you have Windows set to hide file extensions? If so, it won’t show you what the file is actually named.

On the face of it you have the same xml file that I have, however the part quoted is a small section from the middle of a much larger file. I assume that yours is the same?

“Garmin” should be as high in the folder hierarchy as you can get, i.e. (SD card)/Garmin

Maps on the device internal memory (apart from Garmin’s base map) can cause confusion, as can more than one contour map anywhere

You’ve probably read this already and TT Martin will answer emails

The other thing you may need to do – depending on Garmin model – is “activate” the map. On my 810 it’s something like Activity Profile -> Navigation -> Maps -> select the map and activate.

After much fiddling last night it turned out there was something wrong with the img file. I downloaded another GB map from a german site and it work perfectly! Thanks for the suggestions. GPSmap 62s btw

Good FAQ link, didn’t see that. I will have a look at that. To see if there was something else I did wrong.