ETC Response Mk2 DIN Rail Gateway and ETC Echo integration

I am looking for some information about the Response Mk2 DIN Rail Gateway and Unison/Echo integration. I am about to install an Echo system with four dimmers and two relays controlling general LED lighting in a large room. My question is how can I trigger events in the DIN version of the Response Mk2 from the Echo system. Do I need the Echo Integration Interface, Echo Expansion Bridge, Echo Expansion...? I feel comfortable with the DMX configuration on the Mk2 and the associated lighting attached to it, and I feel fairly comfortable with the Echo configuration. I can't find documentation discussing the communication options or handshaking between the two systems. 

"Response Mk2 DMX Gateways offer seamless integration into ETC’s Unison architectural lighting control systems, and also pair perfectly with ETC’s entertainment controls."