Make next button visible after hovering over all images

Mark,

I've attached one way to do it. There are probably more elegant ways.

First, set a trigger to disable the Next button on the slide's timeline starting. (I prefer disabling rather than hiding it so that the navigation doesn't move around).

True/False variables are used, one for each box (or in your case, for each image) included for hovering. The variables are set to True by a trigger when a box (or image) is hovered over. 

Then there is a trigger that you'll need to set the Next button's state to Normal when any of the variables changes, under the condition that all the variables are set to True. So you'll need a trigger for the Next button for each of your images/variables.

I didn't do it in the sample, but you might want to set a Complete state for each of the images so the user can see which ones s/he has already seen, and create a trigger for that state upon hover.

Thank you David

That's working fantastically