Switches were up, down and everything but sideways. I think I will ask them to try and take the TTL converter out of the circuit and see if it will work in manual mode. We actually were possessed like demons trying to get the system working that we failed to do this because we ran out of time for the day and I was leaving the next day. Doh!!!
So the switches were flipped several times and we can eliminate the fact that they could be in a weird mid-position. Your system is in a good place at Cathy's shop, so let us posted with what they will find. Just one last question though: was the bulkhead orange connector plugged in the J2 or J3 connector of the 18915? Have you tried both? BTW I assume that your Sea&Sea converter is an 50106.