From Post #1: 'Maps are unlocked but for enhanced pedestrian mode you need additionally *.unl file generated with Jetmouse Keygen'. In other words you don't need a .gma file as well. What are you trying to so with BC? When do you get a message about needing a .gma? You don't 'convert' the cityxlorer.img 'into' cityxplorer.unl. You need to place both files together into Map folder in root of unit, or preferably the root of a MicroSD card. It's all in the initial post, have another read of it.