In October 2022, on the occasion of the European Day of Restoration, the renowned painting restorer - Mrs Olga von Gregory - presented paintings and graphics by the painter, exile and artist colonist Erwin Bowien in her restoration workshop as well as in the adjacent exhibition rooms of the Waldhof Hackhausen in cooperation with the "Bettina Heinen-Ayech Foundation - Foundation for Art, Culture and International Dialogue". The day was enriched by readings and piano music. The focus of the show was on the restoration of paintings by artist Erwin Bowien. Ms von Gregory is currently the conservator with the greatest expertise in restoring paintings by Erwin Bowien.