Hi Kim,
I've found using the * symbol for CSV imports will produce a bullet point in Physical Description. You may find you have to use | to produce the carriage return to get a list if using CSV, although sometimes entering a carriage return in the text cell will do the same thing. I believe this also works if you are entering directly into the AtoM interface.
I'm not sure if this will work for all free-text fields.
Meribeth Plenert