Has anyone got hold of a 218 yet?

I am still confused as to where it fits in my system and it would take control and send audio to my speakers if insert it between my speakers and my G65. If I am watching TV, and have TV selected on my G65, how would I make the 218 become the primary source in this daisy chain arrangement and start playing MQA music.

It also appears there is not a serial input on the back of the 218 so how would you program it in the same way as you pass setup files to the G65 and HD621?

G65, HD621, 5x DSP5200SE, MC200.