VidyoDesktop - I cannot see other participants but can hear them and they hear and see me

If you are not able to see other participants but can hear and they are able to see and hear you, a good place to start looking is the participant limit feature above the participant layout button.

It is likely that the feature is set to to 0 viewable participants.

The logs would show it as: The participant limit is currently set to 0.

                Line 1048: 06-17 10:12:41.041 INFO  LmiApp        No change in max participant limit 0. (User limit)       [ Media Socket/Timer loop, LmiAppRendererUpdateParticipantLimit, LmiAppRenderer.c:4563 ]

                Line 1048: 06-17 10:12:41.041 INFO  LmiApp        No change in max participant limit 0. (User limit)       [ Media Socket/Timer loop, LmiAppRendererUpdateParticipantLimit, LmiAppRenderer.c:4563 

Simply click on the feature (triangle shaped) and set to auto.