Timeline and Trigger

If you use the built-in seekbar, you won't be able to disable it or hide it.  So you may have to adjust the goal here.

You could add a variable called FoundIt that is set to TRUE when the user clicks the hidden item.  Have this trigger occur first.  

Then change the existing trigger to "Resume timeline when user clicks if FoundIt = True"

Then add a new trigger that occurs .25 seconds after the timeline pause that basically restarts the whole slide.  (Jump to slide (me) if the variable FoundIt is equal to False)  This way they put themselves into a loop if they restart with seekbar.

Another idea occurred to me - timelines on layers.   

Instead of pausing the base timeline, at the key moment you would show a layer that has a massively long timeline.  You set this layer to pause the base layer, allow objects on the base to be interacted.  The layer has no visuals, it's just a long invisible timeline over the paused base.

By doing this, I believe the seekbar will continue playing, it's the layer's timeline that has taken control of the seekbar.

You can put the hotspot in this layer, too.  Then adjust the trigger to simply close the layer when clicked.  This will instantly end the Looooong timeline and resume the shorter base timeline.

I'll try both of these to see which approach work best. As you also indicated, we'll have to discuss what our goal with this project.

For our software training projects, we try to build in as much interactivity as possible to best approximate actual performance. For some of our projects, this includes numerous pauses and resumes and the approach you suggest may be bit of a programming nightmare. It would be nice if the Play/Pause feature in the SL player could be turned off on Slide Properties.

Thanks for your time and response. 

For a HIGH level of interactivity, I tend to develop courses more surgically broken into new slides, layers, etc.  It's less programming to simply come to the end of a short scene and stop, use a layer to pose an "afterthought" question about what we just discussed or a "prethought" question about what is to come next.  Then the NEXT button on those "thoughts" moves us to the next slide where the content continues or the new content is introduced.

More slides isn't necessarily more work.  And you can pare down the MENU listing in the PLAYER settings so if you spread some content conveniently over 5 slides, it only lists the 1st slide in that group on the menu.

Food for thought.