Here's what I have so far but can't get it working... Has anyone had luck.
Yout trigger should be Thermostat changed.
Your first line in your actions should be something like
IF tmp =>xxx
Do your heating stuff
ELSE IF tmp < xx
Do other heating stuff
I would recommend that you look at one of the thermostats that allows remote sensors (like Ecobee) or one that allows off-set calibration (like the Go Control). Trying to "over-power" your thermostat and forcing to do what you want it to do is going to go against it's programming and defeats the purpose of having a thermostat in the first place. It's going to prove very frustrating.
For ~4-5 months now, I've controlled my thermostat using 8 external temperature sensors. It has worked really well, but took a lot of time time to create rules that work well. I posted my rules in the thread linked below: