[HU ist Sebastian]

Hey,

you can automate Step 3 like this:

function my_custom_buddypress_activation_autoactivate(){
	if($key = bp_get_current_activation_key()){
		if($user_id = bp_core_activate_signup($key)){
			if(!is_wp_error( $user_id )){
				$bp = buddypress();
				$bp->activation_complete = true;
			}
		}
	}
}
add_action('bp_before_activation_page','my_custom_buddypress_activation_autoactivate');

I would not recommend auto-login on activation page because it could create a security risk.

Happy Coding!