The whole subject of 'skeletons' is a bit confusing!

The term should properly be applied to the underlying structure of bones, which is something which we can DUPLICATE by copying an existing one. This 'new' skeleton can be scaled up or down, but that is about it for now.

We CAN make new animatiosn to hang on the skeletons, but the Holy Grail of RTW modding has got to be making a completely new skeleton with new bone pivot positions and revised numbers of bones.