How does CSR work in Free For All?

Games Halo 5: Guardians
1

I Have found that even when I do not win games I occasionally level up so does it recognize 2nd and 3rd place as winning?

2

Yes.

3

I think it recognizes the top 4 as a win, obviously at varying degrees and I think I’ve noticed that 5th place neither demotes, nor promotes you. Leaving the bottom three players to be demoted.

4

Usually top half counts as a win, probably applies the same for CSR