Just want to say, thank you so much for this post.
Here I was, spending several days trying to figure out why the GBA emulator would not recognize that an emulated wireless adapter was "inserted" so I could see the Old Sea Map Wondercard. Tried downloading several different versions of VBA, vbalink, etc, but no luck.
With your first four steps, and that version of VBA-M, it all worked perfectly. Thanks! Doing the Old Sea Map event in a Japanese Emerald playthrough with a save that I'll be dumping onto a real JPN Emerald cartridge, and wanting to keep the events/Wondercards as legit looking as possible.