In the Sensor module, you can choose one of the sensors that have been previously simulated in the "Physical" tab using the Equivalent Circuit Analysis.
Those sensors are defined by their very own netlist of capacitances and resistances, as described in the Equivalent Circuit Analysis article.
Those netlists are automatically loaded in the Sensor module, once an Equivalent Circuit Analysis is previously completed.If not, then the Sensor module will be empty and you cannot proceed with an analysis.
When selecting a Sensor from the list, you must then click on "Add Circuits":
Then you must select a specific Equivalent Circuit Analysis and any netlists that belong to this analysis.
Now you are done with the sensor and you can move on to the System Configuration.