Working with Action Fine Tuning with screen recordings

I am working on a project that involves Captured Recorded Screens for Test Me demonstrations.

The captions and the screed recordings were not working well toether, I I tried several things.  Maybe you could explain more.

1.  All the captions default to "Fade In" for Entrance Animation,    Why?

2.  Some of the screen recordings disappeared before the Captions, so I right clicked them for "Show until End",  Why?

3. I used the Action Fine Tuning, right clicking on the screen recording, and moved the white bar close to the green bar.  That seemed to make a more even demonstration.   Why?  What do the white, green and yellow bars mean?

4. Using, again, the Action Fine Tuning, right clicking on the screen recordings on each slide, and unchecked the "Show Animations" check box.  This seemed to be a quick way of moving the white bar to the green.  Now, the slides no longer show screen recording in the timeline, looks like they all changed to hotpots.

I would like to find out more about using each of these settings prior to destroying my project.  HELP

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