Gentlement, what do you advise?
Option 1 - Supply and return of conditioned air approach: Seal the cellar and exchange conditioned air a supply and return approach using 2 or more floor vents/registers between cellar and the main house envelope. Possibly use humidity controlled booster fan in a vent.
Option 2 – Supply only, positive pressure approach: Use one vent pathway only, for pushing conditioned air into the cellar (no exchange with the house). Humidity controlled in-line vent fan.