I've recently installed shufflehax through browserhax, and, to do so, I've formatted my 3DS' SD card. I made a simple backup so I could have all my stuff back, but I forgot to put it back in the card, so the 3DS recognized the SD as empty, so I had to redownload everything I had. At first, I really didn't care, as the games I had were fun to replay, but then I realized I had lost all data on DLC of the StreetPass games (new puzzles, Battleground Z saves). So what I wanted to ask was: can I recover this lost data (I don't care about the other games, just Streetpass) from the backup I made?
