There is no "UK firmware", AtGames only offers updated Genesis-branded firmware.
so how can i unlock SD card slot in my Sega Mega Drive Flashback HD? can you write quick solution? because im newbie with AtGames consoles, and wanted make some custom with game menager app, but havent idea how to start, and dont wanna brick console with firmwares from other regions (if that even possible to brick)... :-/