Ok , your 3D map is unlocked , but I just noticed a mistake in your sd directories

Br47E

"Map" folder must go in sd root
Your folder in sd is named "map", the right name is "Map" with M in capital letter, try to rename it correctly.
Path must be R:/ Map/*.img
directories must be named respecting Capital letters,
Garmin one too.
To check it was not the card I put the files from the SD card into the Garmin/system folder. Still no joy.
Anyway if you tried to copy files directly in Nuvi/.System ,Nuvi should show up them both,
sorry I've no other ideas.