To protect your server with CITECT you can move it into DMZ with transparent mode to LAN (if you need to get it address from one of LAN subnets).
Additional LAN subnets can be added by
1) Objects > Address book > InterfaceAddresses
Add
lan_172_ip=172.24.0.1
lan_172_net=172.24.0.0/16
2) Interfaces > ARP
Add ARP publish of lan_172_ip to LAN
3) Routing > Routing tables > main
Add routes (interface, network, metric)
core lan_172_ip 0
lan lan_172_net 100 (metric same as for lan/lannet)
4) Make sufficient IP rules, like
Allow lan/lannet lan/lan_172_net all_services
Allow lan/lan_172_net lan/lannet all_services