For uninterrupted streaming, internet speeds of at least 100 mbps down and 10 mbps up are recommended. It also highly recommended that the host PC is connected via ethernet. High download/upload latency on your internet speeds can impact streaming as well.
You can check your internet speed here:
https://www.speedtest.net/
In order for Luminar Desktop Capture to communicate on the network, your PC's firewall settings must allow proper permissions. Windows should prompt you for these settings on first launch of the app, but they can be changed by going to:
Control Panel->System and Security->Windows Defender Firewall->Allowed Apps
When installed on Mac, Luminar should prompt to allow necessary access and must be enabled. These can be found at:
System Settings->Privacy and Security->Accessibility