Using WINscp plus to start a ssh host on a windows machine

I've installed winscp plus, and I'd like to allow other scp clients (Unix based) to scp to this windows machine. I can't find any documentation on how this is done.

After I installed winscp plus an info message said that I needed to update c:\program files\openssh\etc\passwd. It told me to look at readme.txt and quickstart.txt. I can not find these documents anywhere.

How can I configure use WINscp as an SSH host?

This is first time I've heard about WinSCP plus. It seems that it is based on some OpenSSH clone for Windows. I have good experience with copSSH (you will find link in this FAQ). It definitely includes the files you are looking for.