Since "Cymbaline" was rehearsed, it may as well have been played. It was, with "Astronomy Domine", a regular of the Floyd's live repertoire in 1970.
You may notice at moments that the audio is out of synch. This is not due to a bad digital transfer or an error in the editing, it seems that when the show was recorded not all the cameras (if any) were recording the audio. Considering how hard film editing can be, some synchro troubles appeared on the original.
The show is shot with three cameras : two cameras on stage (mobile) and one on the left side of stage in the audience (on a tripod). This last one was obviously in synch as you can check on most close up views when either David or Roger is singing / talking.
Most views of Nick are out of synch (slighlty at 06.30 in "Atom Heart Mother" or badly at 16.53 in "The Embryo").
But you can see Roger announcing "This is called the Embryo" in synch and David is singing in synch just after, at 17.19 in "The Embryo", as well as in Cymbaline at 28.25.
As far as it can be checked, Roger is also in synch at the very end of "Set the Controls for the Heart of the Sun", at 48.30.