It sounds more like a pairing issue, you may want to reset the thermostat and pair again. Sometimes rebooting the hub also helps. Using the C-Wire is a great idea because it also puts the thermostat into active repeating mode instead of using sleepy mode. It also helps to do a Z-Wave repair after pairing the thermostat do it can optimize it’s mesh routes and make it more responsive.
This thermostat has a few great features like putting limits on the max and min setpoints. You can configure these advanced features using this Enhanced Z-Wave Thermostat DTH: [RELEASE] Enhanced Z-Wave Thermostat Device Handler with Z-Wave Plus
As for programming the thermostat, you need SmartApps which will do that for you (device handlers only allow SmartThings to communicate with the device itself and configure the features).
There are examples of various apps which can do an wide range of things with your thermostat including using remote temperature sensors, using motion sensors to control the thermostat, creating schedule based on modes or times and much more:
[RELEASE] Motion Sensor Thermostat with Remote temperature sensors, Presence detection and Schedules