my eyes popped when I saw the what later was described as a "mould" . It was regular as far as i can remember whereas rock art is not usually so . was also surprised at the use of burnt mounds for cooking was not even considered .
"was also surprised at the use of burnt mounds for cooking was not even considered" there is a surprisingly large number of suggested uses for the classic burnt mound, not neccessarily exclusive. Myself I believe (http://groups.yahoo.com/group/circlesettler/message/9) that they may have an association with metalworking somehow.