Complex sentence: A restoration of the film was undertaken in 1972, and in 1975 it was successfully shown as the opening event in an exhibition commemorating the 50th anniversary of the Exposition des Arts Décoratifs.
Split into simpler sentences: A restoration of the film was undertaken in 1972. In 1975 it was successfully shown as the opening event in an exhibition commemorating the 50th anniversary of the Exposition des Arts Décoratifs.