Hello Mark,
Have a look at the Marius YO2LOJ post from 6th August 21:47 CEST. It's last minute software made by Marius. You may try this:
http://www.yo2loj.ro/hamprojects/amprd-1.0.tgz
On my Raspberry Pi it works smoothly behind my own router. But... I do not have even tiny firewall up&running.
Best regards. Tom - sp2lob