Complex sentence: On October 9 (in the "Casa Batlló" of Barcelona), it had achieved sales certifying it as 5 times Platinum; it had sold more than 400,000 copies in Spain alone.
Split into simpler sentences: On October 9 (in the "Casa Batlló" of Barcelona), it was certified 5x Platinum by the achieved sales. The album sold more than 400,000 copies in Spain alone.