Sure. The pf.conf is what you are mainly concerned about. Nat.conf is for --- well natting.
I got the link here and the OBSD home page. There is a great tool there that you will love -- an online man page. I use that for looking up shit for pf.conf. It is reallllllly useful. Plus at the bottom is a great BSD forum. It has some really bright Free/Open BSD users there. I personally am rather inactive there.
OpenBSD home page