Allow xmlrpc.php

Yes, just whitelist the xmlrpc.php file by adding the following code to your theme’s functions.php:

/**
 * Filter Force Login to allow exceptions for specific URLs.
 *
 * @return array An array of URLs. Must be absolute.
 **/
function my_forcelogin_whitelist( $whitelist ) {
  $whitelist[] = site_url( '/xmlrpc.php' );
  return $whitelist;
}
add_filter('v_forcelogin_whitelist', 'my_forcelogin_whitelist', 10, 1);