[rich! @ etiviti]

I’ve installed the plugins but when I click ‘Forum Extra’ link in dashboard, the plugins admin page doesn’t show up.

A blank page with just a title (or a WSOD)? make sure you enable the subplugins (ie, BuddyPress Forums Extras – Quote)

If it works, then the Forums Extra admin page would look like this:

Group Forum Extras

Ajaxed Quote enabled.

where do users enter their signatures? I don’t see the field anywhere:

Under the member profile page, click the profile tab, then in the subnav menu – next to Change Avatar is ‘Change Signature’

mybuddypressurl/members/memberusername/profile/forum-signature/