I have AirCam WN-200HD.
I have added the camera and the the preview (Test connection) shows picture well. The picture is there, but it's night and only timestamp could be visible in the upper left corner.

When exiting the setup window the preview, Take snapshot and Stream Video will not work.

Any ideas?
An idea for RTSP
In Home Assistant RTSP feed could be used by installing FFMPEG library to raspberry.
sudo apt install libav-tools
ffmpeg:
ffmpeg_bin: /usr/bin/avconv
setting for RTSP is: -rtsp_transport tcp -i rtsp://user:password@ip_address:554/tcp/av0_0
maybe you can use the similar solution.
Thank you
Br,
Dali