I am preparing unmarried partner visa FLR(m) and have a few questions.
Could anyone can help me please?

1. I have just booked premium service and paid everythig already. Do I still need to fill up the payment part on the application form? Or leave it empty?
2. On the application form question 5.2 "When did you enter the UK?"
I came here 2008 as a tuorist stayed 3 months. Then in 2010 I came here with a student visa. After that I went back to Korea and came back with unmarried partner visa which I currently have.
I have no idea which one I have to write on the form.
3. I have never applied any visa in the UK. The question 1.13 asking me Home Office Reference Number. Does anyone konw what do I have to write?
4. Question 9.15 askeing me to provide the detail of British diplomatic post.
I applied my visa in Korea and I heard my documents were sent to Manila.
Do I have to write Manila visa centre something like?
Please help me.
Thank you.