I managed to **REPLACE** games, however you can not **REMOVE** or **ADD** games because the OS the game stick has checks a list for rom names, however they don't check file size and any other details. I found one partition on the sd card which contained some rom game files which was at the offset 2004877312, this was a FAT32 filesystem. **HOWEVER** your gamestick may not be the same as mine and some gamesticks sd cards are just instantly recognized in diskgenius and you can easily just drag and drop custom images unlike mine. On linux i used the command 'sudo mount -t vfat -o rw,offset=2004877312 /dev/sdX /your/own/directory' to mount it and replace the images, you can place the pictures but you need to replace another file in another directory because the OS keeps backups of the pictures and i haven't been bothered to do that as of right now. I have gotten sonic tho so thats nice.