@ devalian

after re-reading your post

what do you mean

"i put the unlocked img into /Map
and JCV into /.System/JCV"

the JVC is correct place if you place the map on the unit
for me, I place both file on the microSD card

the location as per-below

gmapsupp.img is placed on :SD/Garmin
while the JCV is on :SD/Garmin/JCV

you should try it
or you could try placing the gmapsupp in the .system folder itself and see if that works