Here is a list of the available settings from BuddyExtender and what aspects of BuddyPress they affect. List is current as of version 1.0.1
To find the BuddyExtender settings page, log into your WordPress Admin Dashboard and locate the "BuddyExtender" menu item under "Settings".
Avatar Thumb Size
This changes the dimensions of user avatars in member lists, activity streams and forums.
Default width: 50px
Default height: 50px
Avatar Full Size
Now you can change the dimensions of user avatars in profile and group headers.
Default width: 150px
Default height: 150px
Avatar Max Size
The max width/height of an image the can be upload during avatar creation.
Default User Avatar
BuddyPress uses either the mystery man or a Gravatar for users whom had not uploaded a custom image. This option turns off Gravatar and uses a custom image as a default.
BuddyPress profiles are locate after the members slug (/members/). This setting puts profiles at the site root (url.com/username).
Auto Group Join
Normally, when posting activity in a group you do not belong, BuddyPress joins you to the group. This option allows group activity posting without being added to the group.
Some sign on systems have special characters in usernames that WordPress does not allow. This option allows the use of some special characters in usernames.
Recently, BuddyPress added a text editor to the profile fields when editing a profile. This option removes the WYSIWYG editor.
All Members Auto Complete
When creating private messages, BuddyPress will auto search for members in your friend list when you begin to type. This option changes the search from your friends to all site members. Note, if your site is large the search can seem slow.
Profile Fields Auto Link
BuddyPress auto links some profile fields directly to member search to find similar users with same profile field values. This option turns off all fields auto-linking.
User @ Mentions
Type @, followed by user name, links the username to the user, and sends a notification that they were mentioned in that activity item. This option completely removes the linking and notification. Also, it removes the @ username auto-complete.
Ignore Deprecated Code
BuddyPress loads deprecated code for backwards compatibility. Choose this option If you do not need this loaded.
This option does not allow multiple BuddyPress sites on a Multisite Network. The option allows accessing BuddyPress from other sites on an install.
Root Blog ID
BuddyPress runs on one site on a Multisite Network. This option allows you to choose which site. Default is site one.
Default: main site ID