Directory Plugin Multiple Themes for subsite

I try to set up a yellow page site is use Directory Plugin?

If use yellow page domain is add to that line?

Here you can set the page, to which will redirected the user after registration or login.

Redirect URL (sign in): by default to Home page

Redirect URL (logout):

Where is the best themes / Directory Plugin Multiple Themes for yellow page site ?

So mapping the domain to that page?

Thanks!