I don't think you can have a single button in Interface Builder
trigger 4 actions (like start rendering on 4 different QCViews):
you would need to do it programmatically
i donot use 4 actions the like start rendering 4 different QCViews.
When start app.QCview start rendering.
Now i just changing a movie path at same time.
sorry. i just use to changing a movie .(without start or stop)
The changing have a little delay.
At This case,To lose the gap
Is the program for start rendering on 4 different QCViews necessary?