Garmin nuvi 2567lm howto make it work

Hello.
I want to install OSM map for Poland in my 2567lm device, which has Garmin “southern europe map 15” by default.

I’ve tried to put gmapsupp.img file into Garmin folder on SD card, but the device doesn’t detect the map.
I’ve renamed OSM map to gmapprom.img and replaced oroginal file (in .System directory), but the device says “Maps cannot be unlocked”

Please help.

In some nuvis the default folder is called “Map” where you have to copy the gmapsupp.img into, not in the garmin folder.