Go to the channels palete. Create a new channel - this is an alpha by default. Paste the black and white image into this channel Save the image as a 32 bit TGA
Basically the minigame is off by default but the mod turns it on. Its a difficult case to judge as it comes with the game yet you cant turn it on without a mod...
this is looking really cool pior! just curious what the thought process is on having the spine of the rig in the default position rather than conforming to the model?