hi Snuke
sorry for my poor english
i don't use Humminbird for nav, just for scan
i make my own map with a soft called "Track budy map maker", it take an area in jpeg from Google earth or other system and you cant get this picture in Oziexplorer extension (.Map)
a small soft can convert this picture in .Kap, it's the OpenCpn extension.
I use a pc with Open Cpn and small usb gps recever, it's ok to go every where.
in this picture you can see a part of map made with Drdepht and the Log Open cpn
I get an old
toughbook computer it's all.