I put the 15 VDC supply back and everything is working great. I think the 9 VDC supply may have been on the hairy edge and that coupled with not knowing about the problem with relay 7 and 8 being reversed left me confused.
It’s very frustrating that the companies involved, Simple Home Net and SmartHome, don’t bother or don’t care to publish errata sheets when problems like these arise. I wasted a ridiculous amount of time chasing this problem. How do they get away with it?