Generic bus
Wiring looks good. But you had a good point before, maybe your system needs to be activated on use, and so you have to ring, before the setup.
Are you sure about the wiring because in the generic umet bus setup the purple and blue wires are not “needed” but anyway the circle is spinning and I can’t complete the setup - I will try it when my better half gets home, she will ring 
Then I would say, take out the blue and purple wire, and try without them! Blue is opening and purple is gnd1, and are mostly important for analogue setups!