Forum Discussion
You need triggers that clearly reference a "when" that has a definite specific time, like the timeline of the slide.
For example "Change state of Law says HSRs to Disabled when the timeline starts on this slide", or "... when the timeline reaches xx sec".
Unless what you are trying to do is to disable one button while the layer before it is showing. In that case. put the trigger on the layer: "Change state of Law says about HSRs to disabled when timeline starts on layer Key terms".
If you want the learner to finish one layer before advancing, delete the buttons from the layers, so the only buttons are those on the base layer. Then Set all of them but the first one to disabled. When the learner finishes each layer, have them click something to go on, and use that click action to enable the buttons as you wish.
It would help narrow things down, if you could define what it is that you want.