Yes they did use the church as a garage and, like the Agate Rooms which was used as the officers' mess, it survived largely unscathed - desecrated, but the architectural features are extant. Standing in the choir, I think of Nicholas II who, instead of as is customary, being a parent, leaving the church during the sacrament of baptism, stood in the choir to witness his first born, Olga, being christened.
tsaria