He mustn't have tried it. I tried messing around with Xpadder, and it doesn't change anything.... It allows you to set/emulate the controller with the keyboard, just as you would do in project 64, or which ever emulator you'd use.
I own 3 Hori Mini Pads (Black, Blue, Red), an original adaptoid, a mayflash adapter, a boom adapter and last but not least the adapter from retrousb. None of the adapters work with the Minipads. They all act differently, but none work correctly.