Soooo me and a friend are on Dolphin Beta 5.0-21264, and each of us ran the RiiConnect24 Mail Patcher v2.0 via Homebrew Channel and it worked.
And we changed the DNS in the internet settings to 167.86.108.126 as primary and 1.1.1.1 as secondary.
We even enabled the WiiConnect24 via WiiLink in the config settings just in case.
Then we tried adding each other's Wii Friend Codes to see if we can send mails to each other.
But in the Wii Message Board our names are greyed out and it says "Confirming Registration".
It's been like this since yesterday.
Does it usually take a long time for the registration to go through? Or are the servers down for the time being? Or does this method not work on Dolphin to begin with?