(1) This Part has effect despite anything to the contrary in any of the following (whether made before or after the commencement of this Part):
(a) any other law (whether written or unwritten) of the Commonwealth, a State or Territory;
(b) anything in a trust deed or other instrument.
(2) Without limiting subsection (1), nothing done in compliance with this Part by a third party in relation to a marriage is to be treated as resulting in a contravention of a law or instrument referred to in subsection (1).