I guess that you already know everything about this. However, here is a list of changes specific to me:

• I wanted everything to be automatic: just /etc/init.d/nstxcd start and I should be ready to go
• I use dnsmasq for local DNS proxy (with cacheing) so my configuration use /etc/resolv.conf-upstream

Server setup

More or less standard, expect for fact that my DNS server has multiple IP addresses and I do want to run bind on some of them. So I added something like:

# /etc/bind/named.conf
options {
    listen-on {
        1.2.3.4;
    }
}

Configuring nstx is straightforward:

# /etc/default/nstx
NSTX_DOMAIN="tunnel.example.com"
start_nstxd=yes
ifup_tun=tun0
NSTX_IFACE="1.2.3.4"