The added bones greyed out in the following cases: 1. The image has layers that overlap/are close together; 2. The nodes are not overlaid on the layer.
It is necessary to bind the node to a specific layer.
(Click to view: How to bind skeleton nodes to a layer?)
1. The image has layers that overlap/are close together
In this case, you need to hide a layer when adding bones to another layer. Bind the nodes after adding bones.
Click [Hide] in the layer area to hide the character’s body > add bones to the arms and legs > bind nodes to the corresponding layer.
2. The nodes are not overlaid on the layer
In this case simply move the nodes to the layer.
Click [Select Bone/Layer] > move the node to the layer.