Open the HWinfo Shared memory app, and change the default sensor values in the included .inc file to the ones HWinfo shows for your hardware. Also remember HWinfo /has/ to be running to show any values in Rainmeter.
I'll be doing a proper writeup soon for n00bs like us. I think I understand...
So figured out what was up.
Next question: In the documentation y'all show hardcoding sensor values
However, in the newest release, these values are now strings (for lack of a better word, I'm new at this.)
[HWiNFOCPU0Name]
Measure=Plugin
Plugin=HWiNFO.dll
HWiNFOSensorId=#HWiNFO-CPU0-SensorId#...
Considering the last update to this was in 2016.
Also the "details" link in the sticky is broken.
As is this one. (Makes sense, it's for 2.0, but still in the OP.)
Using the included .rmskin doesn't show me CPU temp either (which is the main reason I'm here.)