New Set up .... Do I need to connect the extension kit??

I have bought the smart Thermostat V3 with hot water control and a number of radiator valves as I already have a boiler and separate hot water tank and a wireless thermostat.
I have set up the bridge, the tado wireless thermostat and 3 radiator valves however I haven’t set up the extension kit. I only want to control my heating with the tado system not the hot water. Do I need to connect the extension kit?
Also the radiator valves work manually but on the app it says no remote access so no temp showing .... but when I go into rooms and devices it shows the all the tado rad thermostats and bridge and thermostat all have a good connection ... I’m confused .... any advice as to how to get the remote access working g would be great!
I contacted Tado via live chat on Monday morning and 48 hours later I’m still waiting for a response 😞