Okay, it appears to be working now as advertised with only power from the USB connector, but I believe that the board has an intermittent connection on it. I can't see any solder joints that look suspect, so most likely it's one of the esp8266 pins.I will just have to handle it delicately. Thanks for the help.

@Marvin-Roger I agree with you that sending each percentage close is a bit to much. But in the case of shutters it often occurs that the final position is not reached (shutter frozen, window open, etc.) So it isreporting only the value reached at actual stop.