About Mapping/ Boygrouping/Video Sync

I guess my way of patching is similar to this comment of joreg

According to this thread the way that I deal with projector setting and camera settings are right. After mapping the videos in subpatches of the server, each renderer goes to fullscreen on its regarded client. It is also ok.
How to combine the videosync with these 4renderers is still an open question.
Answers welcomed…