I’ve found a bug when building the rig from a template on which I’ve changed litteraly everything to be named with a capital leter.
When I build the rig, I don’t know how but the bones was named as “RightHandindex”, “RightHandpinky”, etc, and you can note that “index”, “pinky” and others are created without capitals.
Here is the configuration :
I think i have no other way to customize names so I made a script that I added in Post Script to rename all the finger joints to fix that bug.
If you have another solution, I would be interested !