If you don't hear the faint relay click then power is not reaching the engine.
If I understand correctly, you can use Z-controller without DCSRC receiver and when you apply power you can hear the faint relay click and then the engine starts up (in conventional mode) with sounds about 1 second later. Is this correct?
Confirm you are plugging brick into DCSRC receiver with coax-barrel plug, and then red/black wires from DCSRC receiver to track red/black lockon. If so it sounds like power is getting into the DCSRC receiver (so green LED blinks), but power is not getting through to the track (no relay click). If this is correct, I suggest you pop open the DCSRC receiver (4 black screws on bottom); it comes apart very easily. Then inspect to make sure connections to red/black power jacks on back of DCSRC receiver are intact and nothing looks (or smells!) wrong on the board: