I think I know what you're talking about.
The small square "info" button that brings up the session instructions when you click it, yes?
It does indeed go missing most of the time when you load a saved session that uses it, and I'm afraid it's a bug that didn't get squashed last time around.
It's because the script that displays the info button doesn't get initialised when loading a saved session.
If you go to my website,
TrainzLab, and go to the tutorials section, you'll find the last page of the "Creating and using HTML assets" tutorial explains how you can kick it into action when reloading a saved session.
HTH,
Smiley.