Frame hitch between Cinematic Sequence Devices playing.

You can toggle playback with the TogglePause function on the cinematic sequence device:

    # Store a reference to the active sequence so it can be paused
    var ActiveSequence : custom_animation_sequence = custom_animation_sequence{}

    # An event that signals the active sequence to pause
    PauseSequenceEvent : event() = event(){}

    OnBegin<override>()<suspends>:void=

        # Initialization
        # Set the duration of the sequences
        for(Sequence : Sequences):
            Sequence.SetSequenceTime()

        # Loop random sequences
        sync:
            block:
                loop:
                    if(SequenceToPlay := Sequences[GetRandomInt(0, Sequences.Length - 1)]):
                        set ActiveSequence = SequenceToPlay
                        
                        # Play the sequence
                        ActiveSequence.PlaySequence()

            block:
                loop:
                    # Wait for the toggle pause event
                    PauseSequenceEvent.Await()

                    # Toggle the playback of the sequence
                    ActiveSequence.CinematicSequenceDevice.TogglePause()

If you wanted to cancel the playback you could do something similar with a race condition and GoToEndAndStop.