BuddyPress.org

The app is using the translation strings (with default verbiage) — that’s why you see stuff like __( ‘Leave Group’, ‘buddypress’ ) for example, in the code.

You need to make a custom language file as well as changing slugs in wp-config.php (optionally). Search this forum for more info on how to create a language file and switch it on with bp-custom.php for your install. I recommend getting poedit from Sourceforge to make editing easier.