Complex sentence: MGM was ready to sign Viguié with a contract for four more movies and Frank Z. Clemente, their Director of Latin productions, was going to establish his central offices in Puerto Rico when a copyright dispute over the movie erupted between the Canino family and Viguié.
Split into simpler sentences: MGM was ready to sign Viguié with a contract for four more movies and Frank Z. Clemente, MGM's Director of Latin productions, was going to establish his central offices in Puerto Rico. However, a copyright dispute over the movie erupted between the Canino family and Viguié.