A Unity ID allows you to buy and/or subscribe to Unity products and services, shop in the Asset Store and participate in the Unity community.
Separate names with a comma.
Hippocoder is wrong. It also works with the free version.
I guess it's not possible. Maybe you can do it, but you would have to change the algorithms concerning the detection procedure that come with OpenNI.
You just renamed them? That's not enough, you have to drag the joints onto the corresponding variable (Right Arm, Left Arm,..) in the script,...