why do the stop nav. button hack? and the mute nav. button? quick launch buttons?linear compass?themes? i have the f700bt and learning about it real quick. some of the posts in the hack forums talk about doing certain mods that sound cool but i can't figure out what they are trying to replace or fix. i installed the unit myself, and have done the software and the wire bypass updates and the firmware update from pioneer. i also figured out how to put a custom pic on the startup screen. thanks for any help. james