Internal uci firewall chains are flushed and recreated on reload, so

put custom rules into the root chains e.g. INPUT or FORWARD or into the

special user chains, e.g. input_wan_rule or postrouting_lan_rule.

iptables -A input_rule -i tun0 -j ACCEPT
iptables -A forwarding_rule -i tun0 -j ACCEPT
iptables -A forwarding_rule -o tun0 -j ACCEPT
iptables -A output_rule -o tun0 -j ACCEPT

iptables -I FORWARD -i tun0 -p udp -d 10.9.0.55 –dport 8080 -j ACCEPT
iptables -I FORWARD -i tun0 -p tcp -d 10.9.0.55 –dport 8080 -j ACCEPT
iptables -t nat -I PREROUTING -i tun0 -p tcp –dport 8080 -j DNAT –to-destination 192.168.1.88:8081
iptables -t nat -I PREROUTING -i tun0 -p udp –dport 8080 -j DNAT –to-destination 192.168.1.88:8081
iptables -I FORWARD -i tun0 -p udp -d 10.9.0.55 –dport 1935 -j ACCEPT
iptables -I FORWARD -i tun0 -p tcp -d 10.9.0.55 –dport 1935 -j ACCEPT
iptables -t nat -I PREROUTING -i tun0 -p tcp –dport 1935 -j DNAT –to-destination 192.168.1.88:1935
iptables -t nat -I PREROUTING -i tun0 -p udp –dport 1935 -j DNAT –to-destination 192.168.1.88:1935