I now have it working in Chrome on my Surface Book running WIn10.
Fix was turning acceleration on. I had to turn it off for something I was doing in the past, don't recall what, but it's on now and the heatmap page loads.
Now to figure out why it's still not working on the Mac! (Acceleration on Mac's Chrome is already on).
Support ticket hasn't been much help. They don't know why it's broke on my machine either. FWIW: It's not my account related.