Hello,
Before the host starts the meeting, join the meeting using Customized UI Mode and enter the waiting room. When the host starts the meeting through the Zoom client, the Customized UI will continue to display or flicker the camera feed, preventing the Meeting main interface from being displayed.
I tested v6.2.3.47557 and v6.2.0.46750 and both have this issue. Please check and fix it, thanks.