SORRY IT FINALLY FAILED! Steps: 1. Run a game DL Play supported (such as Mario Kart 7, Luigi's Mansion 2, some VCs like Battle City, etc.) with SOURCE 9.2 console - Only Digital version works! 2. Start a multiplay. 3. Run DL Play with TARGET console, choose 3DS mode, then enter the multiplay SOURCE console hosted. 4. Upgrade TARGET's firmware when the dialogue appears.