IMO, in case of CSA (ISDA) we see an outright transfer of title in collateral by the counterparty that is required to provide collateral. So no need for court for secured party to get ownership of collateral.
Could you please explain what kind of zero coupon bond we take for mapping? I mean Is it OK to replace corporate portfolio risk with government zero? There is no information of quality type of zero bond for mapping in any source.