Search Widget - unable to set property description error

[TaupoDistrict_Council]

I'm trying to set up our first search however I'm getting an error message which I can't figure out.

I've set up the portal within the datasource and the service of interest within that.

I've tried both the default popup configuration and the custom one.  However I get the following error message: 

What am I missing to make this work??

Below are the screenshots of the process I've taken.