Buttons faltering

My buttons which are set up to find a certain page works
95% of the time. Occasionally a new one, even though properly
set, will not go back on a preview window. Sometimes it will
go to that window once, but will not go back. I checked everything
I know and they are all setup the same. What could this be?
Also is it possible to get rid of a section without getting rid of the pages?

Could it be that another element like a box or something is sitting on top of the button blocking some of it from being clicked?