Complex sentence: Its production was somewhat controversial because the surviving families of the astronauts generally objected to its production and the point of the film is the safety inspections and arguments surrounding the use of the o-rings that ultimately were blamed for the explosion.
Split into simpler sentences: Its production was somewhat controversial because the surviving families of the astronauts generally objected to its production. The film concentrates on the safety inspections and arguments surrounding the use of the o-rings that ultimately were blamed for the explosion.