Change state of an object, when all layers have been visited independently from order.

Hi Phil,

Thank you for your help - it has already brought me further!. Currently the buttons are on each layer, to allow a jump from layer 1 to layer 2 directly, without jumping back to the slide. I am now confronted with the issue, that when using this trigger, buttons (on slide but also on layer) should be all visited. 

How would it be possible to have activ button on the main slide only, but still make them clickable and hence visted on the layers? 

Thank you!