I have been having 2 issues as I try to use the Advanced Biped template in the character object. I'm sure my issues are inexperience with rigging itself, but hopefully someone can give me a brief explanation of these.
First, when I add a hand and fingers to my rig, none of the symmetry works. It works great for the legs, and arms, but breaks down at the hand and fingers. I end up having to adjust both sides separately. Next issue is what I think is just a display thing that I have to wrap my head around. In the biped template, if I add fingers, they curl as expected, but in the advanced biped template, there seems to be additional joints above the fingers. I'm wondering if these extra joints are there to help create the extra parameters available in the ab template? If so, Do I ignore those joints for weighting? Here is a screen grab of what I'm talking about.