@Zenitwhen you talk about outbound NAT "my other network 10.255.255.0/24 comes out with IP 82.14.25.56", that is something that unfortunately the MX range does not do, you only have the option of 1:1 NAT as @KarstenI said, this is usually used for say a mail or web server hosted inside your network that you do not want to be on the main public IP address used by the outbound general internet traffic.
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