I have discovered a bug or design flaw in the Amcrest Smart Home software. I documented it in detail here: https://amcrest.com/forum/viewtopic.php?f=32&t=14973
The issue is this: If your device running the Amcrest Smart Home App is on your home wireless network, but your home network has multiple subnets with a router, and you have setup the Doorbell Cameras to be on a different subnet as the camera, then the app cannot connect. This is not a network or firewall issue, but a design flaw due to using un-routable broadcast packets for camera discovery and providing no alternate method to discover the camera from the app.
That prior thread is locked and that is why I'm posting this here to follow up on the results from support contact I mentioned in the other thread. Here is the update.
Amcrest support would not remotely connect to my PC/network to review the issue and apparently they do not know enough about networking to properly replicate a routed layer 3 internal network. Amcrest also won't be fixing the proven issue. All they need to do is allow me to input the local IP in the software rather than attempting to discover it every time, but they won't even be doing that. I am VERY displeased with Amcrest and will NOT be buying any products from them in the future.