Ive been tinkering with the 500-in-1 game-elf SD card.
One problem im having is as soon as i alter the gamelist it go's into a re-boot cycle
even if you just alter 1 letter its bizzare.
But you can access the game edit section and any roms you have added and altered the gamelst.cfg to show your new rom . the added rom/game will show up ok but when you exit it follows the re-boot cycle again.
im more looking at adding my own selection of roms rather than getting round the serial number
items ive added are ROM/Snap/cfg/nv ram
ive managed to clone the card easy enough that boots and plays ok , and this comes in handy for tinkering with with no comeback if i mess up.
if you require to write to the sd through ubuntu just bring up the terminal and type sudo nautilus
then your password , it will warn you there is insufficient space but write anyway and it does the job .
reagards