Śrī Matre Namaḥ:
I don't recollect Guruji talking specifically about the differences between Durgā and Camuṇḍā. May be someone else can chime in here.
There are number of research papers and books written where her iconography and nature is described. Below I provide a sample of those.
from David R. Kinsley's “Hindu Goddesses”
A hymn of praise to the goddess Camuṇḍā in Bhavabhūti's Mālatīmādhava describes her as dancing so wildly that she threatens to destroy the world. She has a gaping mouth, wears a garland of skulls that laugh and terrify the worlds, is covered with snakes, showers flames from her eyes that destroy the worlds, and is surrounded by fiends and goblins. In Ratnakara's Haravijaya the goddess Camuṇḍā does a dance that destroys the world. As she dances she plays a musical instrument whose shaft is Mount Meru, whose string is the cosmic serpent Sesa, and whose gourd is the crescent moon. She tunes this great instrument during the deluge that destroys the world and then plays it during the night of the end of the world.
…Camuṇḍā is also typically described as haunting cremation grounds. In the Mālatīmādhava of Bhavabhūti a devotee of Camuṇḍā propitiates her in a temple adjacent to a cremation ground. A South Indian image of Camuṇḍā is described as follows:
"She holds a skull-mace (khaṭṭvāṅga), a snake, a wine cup (modaka bhāṇda) in her different hands. She has a third eye and below her is a jackal gnawing at the left hip of a corpse lying on the floor.”
…These goddesses are also often described as lean, skinny, or emaciated. They are also said to have prominent teeth or fangs. There is a clear emphasis on these goddesses' ever-hungry and all-consuming nature. They rip and tear their way through the world, seeking to satisfy a primordial hunger that is the opposite of the ever-fruitful forms of the Mahadevī, which perpetually give birth to all creatures. Some of the terrible goddesses have epithets that emphasize their hungry natures. In the Devī-māhātmya the Devi mentions one of her incarnations named Raktadantikā (the red-toothed one) (11.42). The goddess Danturā (she having fangs) is described as having "bare canine teeth, rounded eyes, ghastly smile, emaciated body, lean and pendulous breasts, sunken belly and peculiar sitting posture." An image of Camuṇḍā adorning a temple in Bubhanesvar is so emaciated in appearance that her bones are all clearly visible. Her eyes pop from her head, her breasts are withered, and her expression is fierce. Another awesome image of Camuṇḍā is found at Jajpur in Orissa. She is described in this sculpture as follows:
She has four arms, emaciated body and shrunken belly showing the protruding ribs and veins, skull-garland (muṇḍamālā), her corpse seat (pretāsana . . . ), bare teeth and sunken eyes with round projecting eye-balls, bald head with flames issuing from it. She holds in her back hands a kartr (chopper) and a sula, while her front right and left ones hold a kapāla and a muṇḍa (human head) respectively; the skull on the armlet on her right hand has a grinning smile on its face, while the severed head in her left hand has a life-like expression.
from "Early Medieval Representation of Human Anatomy: A Case Study of Chamunda Stone Image from Dharamsala, Odisha"
http://www.heritageuniversityofkerala.com/JournalPDF/Volume5/11.pdf
The goddess Chamunda is an integral goddess in a group of Saptamatraka placed her on the seventh number in several texts (Rao 1914; Banerjea 1956; Joshi 1979; Mukhopadhyay 1984; Misra 1989; Pannikar 1997). The iconographic development of this matraka imagery is discussed by several scholars (Banerjea 1956; Kinsley 1975; Joshi 1979; Mukhopadhyay 1984; Misra 1989; Pannikar 1997; Miester 1987). However, its individual iconic representations and presence in the group of matrikas are observed being prominent onwards 4th century CE. The several findings of the images of Saptamatraka after 4th century CE in throughout Indian subcontinent indicates that the worship of goddesses was prominent during the Early Medieval period (Kinsley 1975; Meister 1978; Pannikar 1997). During this period these goddesses are seen portrayed in two types. In a panel which varies in numbers such as seven, eight or nine and individual depictions. Its myths and legends, the number of goddesses, its origin and followed by their inclusion and exclusion are discussed in plenty of texts. This corpus of texts also conveys the religious and sectarian importance (Rao 1914; Kramrisch 1974; Kinsley 1975; Dehejia 1986; White 1996).
As mentioned above the iconographic depiction of Chamunda also seen in two types. In an early phase of her iconographic depiction, she is shown in ferocious form but with usual feminine features. In several instances, same has continued in the latter period also (Kinsley 1975; Meister 1978; Joshi 1979; Misra 1989: 102; Pannikar 1997). However, this scenario gradually changed significantly and along with this, the goddess began to be represented in skeletal form (Kinsley 1975; Meister 1978; Joshi 1979; Misra 1989; Pannikar 1997).
The several names of the goddess also make some confusion regarding the exact nature of the deity. As she is referred as Chamunda, Chandi, Kali and Kalika. However, the textual tradition is clear on one aspect that the goddess is a manifestation of goddess Durga (Agrawala 1963; Kinsley 1975; Joshi 1979). Whereas, its mythological background strongly connects her with the Shiva which is vividly described in an episode of andhakasuravadha in Agni Purana (Agrawala 1963; Hazra 1963; Kinsley 1975; Misra 1989).
The Iconography of Chamunda
The goddess was instrumental to kill the demons Chanda and Munda hence she named as Chamunda. The deity is known for her ferocious nature and mentioned as a consort of Bhairava who also bears ferocious character. The deity isalso considered as a goddess of death and time (Kinsley 1975). There are multiple aspects which are discussed in the texts due to this the fearful nature of the deity developed as its identical element. This ferocious element seen represented through the skeletal body, with a terrifying face, sunken eyes, gaping mouth, pendulous breasts, long nails and a sunken belly surrounded by flesh and bloodthirsty wild animals. The mount of the deity is a preta (corpse). Some opinions vary which claims that it is not a preta rather it is himself Shiva who laid beneath her in order to get her to calm down from anger after killing a demon (Soundarajan 2003: 267‐71).
There are eight principle forms of the goddess Chamunda. In these most commonly observed iconographic features of Chamunda can be extracted through the texts of the iconography. That is the goddess should wear a garland of skulls (mundamala), with jatamukuta formed of matted hair, tied with a snake or skull ornament. The goddess holds a bowl in her hand filled with blood or wine. The deity should be shown surrounded by a skeleton, flesh‐eating jackals, corpse, snake, eagle and scorpion. The mount of the deity prescribed varies according to its regional affiliation and textual tradition (Mukhopadhyay 1984; Misra 1989; Pannikar 1997). Some of the texts prescribed owl as a mount of the goddess. Whereas, most commonly mentioned and noticed mount is a corpse. The goddess is called Yogeshwari when the deity is depicted with three eyes and four hands (Rao 1914; Misra 1989). The attributes of the goddess are prescribed as follows, the trident or dagger, kapala, damaru, and narmunda. Sometimes a scorpion can be seen depicted on her navel often noticed when the deity is shown in a dancing posture. The ornaments of the deity are mentioned to be made of bones, serpent, skulls and other symbols of disease and death. The deity should depict wearing a yajnapovita, made of skulls (Rao 1914; Banerjea 1956; Joshi 1979; Pannikar 1997).
