Well, the people who have custom DLC, have been to someone who has DLC's town, and/or have gone to someone's town who has once visited someone with custom DLC's,won't see it as Nintendo's DLC but will see it as the item that has the "code 1111" However, people who don't have custom DLC, been to someone who has DLC's town, and/or haven't gone to someone's town who has once visited someone with custom DLC's, will see Nintendo's DLC instead of the custom one. Also there are only 256 slots i believe that we are currently sharing with nintendo.