@pike If you were able to merge the line chart into the underlying bar chart (ex a blue bar instead of a blue line), you'd get a lot off-the-shelf
for the mouse over, you can also work the the Scene. I think you're going to end up doing a lot of pick correlation. For example, "hover over the resized 3rd drawn rectangle". The top layer of the stackpane -- whatever it ends up being -- doesn't pass mouseover events to the sibling layers. Rather, they capture/bubble to parents (which can then delegate).
So, you can put handlers on the Scene and get the effect i think you're after too. there are some scene/local conversion functions that can help