I've updated the website with a new tutorial for developing binary message formats for use on MQTT. The new tutorial demonstrates using Argot to send messages from a Java host over MQTT to an Arduino with an Ethernet shield.
http://www.argot-sdk.org/tutorials/arduino-mqtt-argot-blink.htm
The demo was based around the previous demo which was based on the basic Blink Arduino sketch. It turns out that the Ethernet shield uses Pin 13 which makes the LED on Pin 13 unusable. Oops. 
While this tutorial shows how to write a protocol using Argot to make an LED blink at different rates, the LED doesn't actually blink. The demo still communicates back messages via serial so hopefully has enough to show the basics of Argot.
I've also released the Argot core library in Java as version 1.3.b4 (beta 4). I've got more demos planned and documentation. I'll update when I release more.
David.
@ArgotSDK