Tim,

Here's what I have done:

I have a G68 with legacy speaker outputs, so I use an AC11, but I believe the concept should be the same.:

Legacy L+R and comms from G68 to AC11
SpeakerLink Master from AC11 to 218
Network in to 218
SpeakerLink out on 218 to left and right front speakers (I use home runs)
Set both G68 and 218 to "Auto"

Works perfectly. Comms seems to work fine. remember, with DSP speakers, volume is done in the speaker itself, so both sending the command hasn't been a problem. I have a feeling the G68 comm is controlling the rear volume and 218 the front.

So, for you it should be:

Connect the master Front SpeakerLink OUT of the 861 to the SpeakerLink IN of the 218
Connect the network input to the 218
Connect your front speakers to the 218, either daisy chain or home run.
Configure 218 for SLS on network and all other inputs SpeakerLink
Set both 861 and 218 to Auto

That should do it. I didn't even have to reprogram my universal (RTI) remote. The 218 doesn't require IR input as the comms comes through SpeakerLink.

Have fun!
John

Main system: Cable, Apple TV, HD621, G68D, AC11, 218, DSP7200SE (L+R), DSP3200 (L+R Rear)
2nd system: Cable, Apple TV, MC200, HD621, 568.2, M3100 (L+R)