enable-username-availability-checkwith-simple-modal-login.php

function buddydev_ua_enable_everwhere( $load ) {
	if ( ! is_user_logged_in() ) {
		$load = true;
	}

	return $load;
}
add_filter( 'buddydev_username_availability_checker_load_assets', 'buddydev_ua_enable_everwhere');

function buddydev_ua_custom_selector( $selectors ) {
	return $selectors . ', div.simplemodal-login-fields input.user_login';
}
add_filter( 'buddydev_uachecker_selectors', 'buddydev_ua_custom_selector');