Change all of the settings in this screen back to how they were by default:
http://i.imgur.com/2nxDqfO.png
Next, in the Dolphin options, change this setting:
Options > GameCube > Slot B > Memory Card
You should get the Action Replay menu after that.
http://i.imgur.com/2nxDqfO.png
Next, in the Dolphin options, change this setting:
Options > GameCube > Slot B > Memory Card
You should get the Action Replay menu after that.
