BuddyPress.org

Try this…
Create bp-custom.php, it will go in /wp-content/plugins
Add this code to it, change “/login-or-join” to whatever your page name is :

function login_intercepts(){
/*  if not logged in, user is sent to another page  */
if ( !is_user_logged_in() ) {
bp_core_redirect( get_option('siteurl')."/login-or-join" );
}
}
add_action( 'wp', 'login_intercepts', 3 );