Complex sentence: The Residenztheater, or "Cuvilliés Theatre" (1751--1755) designed and constructed for Elector Max III Joseph by Cuvilliées; though the theatre was bombed during World War II, the carved and gilded boxes had been dismantled and stored for security.
Split into simpler sentences: The Residenztheater, or "Cuvilliés Theatre", (1751--1755) was designed and constructed for Elector Max III Joseph by Cuvilliées. Though the theatre was bombed during World War II, the carved and gilded boxes had been dismantled and stored for security.