How Do I score a Diamond status on a song in Karaoke Revolution Party for PS2?

a.) Hi. I'm trying to finish Karaoke Revolution Party on PS2. In order to unlock my goals, I need to achieve a diamond status on a couple of songs. I bought this game used from Gamestop but it came with no instructions. b.) And also, after I finish a song it doesn't save my high score...any suggestions of what I could be doing wrong?How Do I score a Diamond status on a song in Karaoke Revolution Party for PS2?check www.gamefaqs.com. They will have it.

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