So I followed the guide on the 3ds guide hack website to succeed in installing cfw to my old 3ds xl. Soon after, my little brother wanted to play mario cart ds with me and he used a flash card and I used ds download play on my newly hacked 3dsxl. However, when booting up into ds download play i would get a black screen and eventually I would be sent back to the home screen. I formated the sd card and I lost all the custom files and the problem still persists. Thank you to anyone who can assist me with this problem.