The little figure being the "human" form of Asura Mahisa is common knowledge for some longer time already.
Here two of the more recent papers, handling the Durga/Uma/Rangda/Calon Arang topic, in their entirety:
http://nirc.nanzan-u.ac.jp/nfile/303
https://www.academia.edu/35754671/We..._Durga_in_Bali