Smoothwall Express 3.0 with Multiple NAT

This is a must have for any Smoothwall Express Setup. This mod gives you full control of your interfaces including multiple IP addresses, ports and mac control:
The mod gives ultimate control with the following:
1.   Specify origin source IP/Network
2.   Specify the origin/destination ports to be open for your specific IP/Network
e.g. Open access for the IP 222.111.55.333 on port 57 to your IP xxx.xxx.xxx.xxx on port 22
To install the mod simply run the following from command line:
1.  wget http://stans-smoothwall3mods.googlecode.com/files/fullfirewall-3.3.3.1-Express-3.0-i386.run
2.  sh ./fullfirewall-3.3.3.1-Express-3.0-i386.run
**NOTE: Smoothwall Express 3.0 should be up to and including update 9 – Maintenance > Updates.
Log back into the Smoothwall GUI and you will now see the Full Firewall Control interface.
For further reading take a look at below link: 
https://www.linuxtutorial.co.uk/tag/smoothwall/