How is formula 12 derived from formula 7?

[syf0518]

Thank you for your contribution, it's wonderful.In the article, the score function in the reverse SDE in (7) can be replaced by (11),but I don't know the specific derivation process.Can you explain exactly how it was replaced?I'll appreciate it if you could tell me.

[ernestchu]

I have the same question. Additionally, what does $W$ stand for in (12)