Don't use bb.sh
Plug in your bunny and use this:
#!/bin/bash
ifconfig eth1 172.16.64.64 netmask 255.255.255.0
iptables -X
iptables -F
iptables -A FORWARD -i eth0 -o eth1 -s 172.16.64.0/24 -m state --state NEW -j ACCEPT
iptables -A FORWARD -m state --state ESTABLISHED,RELATED -j ACCEPT
iptables -A POSTROUTING -t nat -j MASQUERADE
echo 1 > /proc/sys/net/ipv4/ip_forward