Applying changeset 18651 does not fix the uploader. Now you get a 'Invalid json' error in a popup.
Perhaps you forgot to comment out lines 89 & 90 in /plugins/moxiemanager/classes/Exception.php
/**
* Registers the error handler and treat everything as errors.
*/
public static function registerErrorHandler() {
// @error_reporting(E_ALL);
// set_error_handler(array("MOXMAN_Exception", "throwRuntimeError"));
}