I had all those settings configured. Finally found what was missing while looking through one of your other posts on the problem. On the NVR settings->storage->schedule there is a tab to set the snapshot recording schedule, that was not scheduled at all before. I now get emails triggered by a...
Got the same problem with my setup. Dahua NVR4216 using PIR to trigger alarm. Sends start and stop emails but no snapshot. When I was using motion video detection on the cameras themselves, they would send snapshot emails. To many false alarms so I switched to using a PIR connected to the NVR...