(1) The validity of the purported custodian's designation;
(2) The propriety of, or the authority under this article for, any act of the purported custodian;
(3) The validity or propriety under this article of any instrument or instructions executed or given either by the person purporting to make a transfer or by the purported custodian; or
(4) The propriety of the application of any property of the minor delivered to the purported custodian.