You
            can add multiple Subtitle XML clips to a timeline, then mute all
            but the layer you want to process. With this method you can quickly
            version a clip.
         
         To work with multiple Subtitle XML layers
            in the timeline:
         
         
            - Stack multiple Subtitle XML clips onto
               layers of a timeline.
            
- Hold Ctrl and
               click the track identifier on all the layers you want to mute.
               NoteA muted layer has
                     a yellow track indicator.
                   
- Drag the timeline onto the Clip Library
               box to save the clip.
               The clip is saved with
                  only the selected subtitles appearing.
                
- Repeat steps 2 and 3, alternating the
               subtitles that appear. To show a muted layer, hold Ctrl and click its track identifier
               again.
               TipThe top layer cannot
                     be muted.