How can you open individual slides in captivate 10 video?

Ruth, I accomplished adding text captions, boxes, moving stuff, etc. to a video using Camtasia Studio.  This is what you need, the editor allows you to see the entire video in the timeline and then you add the necessary text boxes at the exact time.  The are superimposed over the video.

Now, I just tried with a sample video and just do exactly the same thing as in Camtasia.  See the text caption starting at 2sec and ending at 4sec in the timeline?  That will display as a superimposed object over the video.  you are not editing the video as Rod explained, you can't do that. But you can play the video and show other objects in front of it.  Just play with the timing and length of the video.  I hope this helps.

May want to put more content in your post itself. I'm not too comfortable opening a Word doc from an unknown source online.