I followed the wiki for setting up a wiimote, and am using the ir functionality, which makes this MD a incredible upgrade to my current setup using an xbox with XBMC. When the MD boots into the orbiter, and I connect a wiimote, I can only scroll through the bottom left 1/4 of the screen. Others have noted this problem as well.
For me the resolution was to use the default ir_ptr (with the tildes "~") and to add the xorg.conf lines described here
Option "Name" "Nintendo Wiimote"
and to the ServerLayout section
InputDevice "Wiimote" "AlwaysCore"
Also, I removed the mac address so that any of my wiimotes can connect. So far, so good. Now if I can get sound from my Audigy card, I can start using this MD!