The start of the mouse path is based on the end point of the mouse path on the previous slide.
If there is no mouse on the previous slide, I believe the mouse will either start from top-left by default, or possibly from where the cursor was last show on any previous slide that did display the mouse (though I'm pretty sure it's the first; top-left).
You have to be sure 'show cursor' is enabled for any slide you want the cursor to be visible, and in order for the mouse path to be shown.
Right click the slide in the filmstrip and check the cursor/mouse options.
Caption show/hide timings are dependent on the start/stop times of those objects on the timeline. If you need the second caption to delay a bit longer so the first can finish displaying, move that second caption object further down the timeline.