Complex sentence: Upon release, the album received mixed reviews; it has been reported that the album was one of Creation's lowest selling albums, shifting only 500 copies, but in fact the album actually sold over 20,000 worldwide.
Split into simpler sentences: Upon release, the album received mixed reviews; it has been reported that the album was one of Creation's lowest selling albums, shifting only 500 copies. But in fact the album actually sold over 20,000 worldwide.