I think you didn't miss much for not understanding the Japanese nor the Chinese substitute.
What Yoshiki talked about was more or less the same - about his childhood, how sick he was, how he got the piano from his parents, how his father's suicide affected him, how the classical music influenced him, how he formed the band, how he got the band members, how he bought the studio in L.A., how hide's death affected him.....etc. Actually more or less the same thing you can watch from that X movie.