/ip firewall filter remove [f]

/ip firewall filter add chain=forward connection-state=established,related action=accept
/ip firewall filter add chain=forward action=accept src-address-list=Optimus dst-address=192.168.0.55 port=1433 protocol=tcp
/ip firewall filter add chain=forward dst-address=192.168.0.55 action=drop



/ip firewall nat
remove [f]
add action=dst-nat chain=dstnat protocol=tcp to-addresses=192.168.0.55 to-ports=1433
add action=masquerade chain=srcnat out-interface-list=WAN