[werk_ag]

... Note, I do not have any temp sensor connected to the WDisplay.

This don't cause any problem, just set that option in the user configurable options. (To receive inside temp/ hum data from the receiver unit set this option to 0).

Code:

// --- Use local TH sensor or Main Station TH sensor for Inside Temp / Hum display
#define UseLocalTH_Sensor     0    // 1= Local TH Sensor, 0= Main Station TH sensor

Please check this, by default it is at 1.