Lightbox automatically reopens when with seekbar

I know this post is a little old, but I found a pretty good workaround for this issue. Instead of triggering when the timeline reaches a certain time, I've added invisible cue boxes (orange lines in this case to illustrate) for a duration of .25 sec at the points I want the lightboxes to appear. The trigger is then to lightbox the slide when the state of the shape is normal. You can then scrub the timeline around at will, though if you get too close to those points, there may be some overlap of lightbox over video.

You can then scrub the timeline around at will, though if you get too close to those points, there may be some overlap of lightbox over video, instead of the expected pause (if that's what you are going for). 

I'm guessing that using the "when timeline reaches x" condition does not work because when you scrub the timeline, it is considered that you are triggering all times previous to that point as well.