@felmue Yes. This time I erased first, and it completed successfully. I reset it afterwards, then put it into download mode again (flashing green led) and then burned the Atom S3R UIFlow image. It burned successfully.
When I clicked the reset button, it found COM4 and COM5 (it usually just has COM4) but still no screen.
Now I think I have it working. I think maybe I assumed it would load a program to the screen for UIFlow, but I guess it doesn't?
Is there a good place to get more S3R programs? I only see the UIFlow one in M5Burner?