The Heatmap only shows up once you have reviews in the cache. Since you have it on two machines, it would not show up on the 2nd until you do reviews on the 2nd. You might want to read through this thread for a bit to get a better idea, but basically the script is currently unable to sync reviews across different devices, i.e. reviews you do on one device will not show up on the others. This is because the API endpoint needed to do so was disabled over a year ago.