I’ve added the temperature icons as well as a couple of config options for low and high temps, tempLowValue & tempHighValue. They default to 65 & 80, so you’ll want to set them to your celsius values. Icons will be green for between low and high (normal), blue when low, and red when high.
If you’ve already installed, besides adding the two config options you just need to change to the ~/MagicMirror/modules/MMM-Smartthings folder and do a git pull
No need to run npm install as the dependencies haven’t changed.