How to custom ROI

Hello,

First, sorry for my bad English.

I once got an analyses through CONN, but I couldn't divide seeds in more detail.
For example, I wanted to divide hippocampus to anterior hippocampus/posterior hippocampus
and analyze each of them as a seed.
I have no idea about how to divide it, and on which step should I custom the setting?
(I mean setup, denoising, analyses, and results)

Thanks,
Minho Kang