Hi Erwin,
ZF7372 has already reached end of sales and end of software maintenance.
RMA will be ended on 31-Dec-2021.
SZ/vSZ with R3.6 and earlier release support ZF7372, but R5.0 and later release do not support it.
You can find detailed information in EoL announce of ZF7372 and Release note of SZ/vSZ.
Regards,
Masaaki Yamada