Ok, new question just now: I'm trying to get two games, Pokemon Black and White, to connect on the Hi-Link since I want to visit the Black game's Black City in order to make grass patches and water show up in my White game's White Forest. I know these DS's can connect since I just used them to trade Pokemon with each other. Yet, when my characters go to the bridge in Hi-Link, the connection bar is red and even after letting them sit a few minutes, there is no sign of them establishing a connection with each other. I even tried all combinations involving going to different ends of the bridge, but still no success. The only explanation I can think of is in the Black game the character has only just made it to Hiun ("Castellia"?) City for the first time (2 badges), where as in the White I've beaten the story and visited every location, including White Forest. Maybe the Black game character has to visit Black City first?
EDIT: Ok, looks like we can't both be in Hi-Link at the same time. My White guy is in White Forest, and my Black in the Hi-Link. I got through the bridge portal, but there's nothing to do there. I wandered all over and all I can do is talk to the elderly man about missions or go back to my normal world. Plus, I'm worried I may need to have my Black guy in Black City and my White guy in the Hi-Link to make grass appear in my White game's White Forest, but as I said, my Black character is far from unlocking that part of the game. :-/