Quick clarifying question. Are you saying you want all 4 panelists to be able to have their videos appear at the same time while you are presenting content in the viewer window? We sometimes pop-out into full screen video mode when we do large group debriefs/discussions and ANYONE can be on video at that point. However, when we are simply sharing content, it does seem to be the only one panelists video shows at a time in the video pane in the participant panel (it seems to be whoever is speaking, sow e are careful to mute our mics when not speaking so our webcam doesn't steal the show).
Not sure if I have captured your questions accurately, so feel free to clarify.
Eric