Yes it does, they both have the same sensors (temp, humidity, motion)
There are a few options for what it will do, There is a ‘threshold temp difference’ you set, this is for if the reading of the sensor and thermostat get too far apart. Say you set this at 5 degrees and the two become 5 degrees apart, if it is set for savings it will stop trying to increase that room to save money, if set to balanced it will continue heat/cool until the average of the room and thermostat reach the set temperature on the thermostat, if set for comfort it will continue to run until the room sensor reaches the set temp. In the case of the comfort setting and your example, the main floor could get cold.
I think what you may be referring to is setting a schedule for when the sensor is included, for instance if you have a sensor in your bedroom you may only want it to look at that sensor when you go to bed, so you can have the sensor be included in the sleep mode of the thermostat and excluded in the home and away modes.
Hopefully i was able to answer some of your questions