Currently in Graph Builder, when using box plot and points graphs combined in the same graph, the box plots properly segregate into "series" when a category is added to 'overlay' but the points do not overlap their coresponding box plot and are instead jumbled. It is as if the box plots have an hidden overlap variable set to 0% (terminology from excel bar graphs) but the points have a hidden overlap variable set to 100%. There are a few ways to fix it, but are either not exact, or take a lot of work to properly format the image, changing box plot colors for proper grouping, and requiring an extra legend to be added. Here is a post with pics refrencing the effects.