Rig, try adjusting the color palette in the IMAQ WindDraw function (i.e. 255,255,255 instead of 0,0,0). That should get rid of the all black image from the IMAQ Skeleton. Also, make sure you have a border width of at least 1 (IMAQ ImageBorderSize) on the image being sent to IMAQ Skeleton.
Good luck,
Steve