No, Real quick lets make sure one thing.... depending on what card your using you do know you may need to save, turn off your DS, then turn ON your DS go to the loader screen then turn off the DS. (This tactic is needed for G6, M3, and some other cards)
Anyway once you add the wondercard to your save you should go to a Pokemart ( THE BLUE ROOFED buildings) and see a guy wearing a green shirt and hat in front of the counter.
Ah, ok. Using a SupercardDSone, so I shouldn't see this Mail Carrier dude until AFTER I edit my .sav file then? Makes sense, gonna give it a try...
EDIT: Tried it, but nothing happened. I have an open slot and everything, I walk into the Pokemart, but the only people that are there are the two Pokemart girls behind the counter and the usual two random customers.
Perhaps this is because this is my first time using Pokesav... n00bystyle?