Method to pick planeprimitive in "pile"

Hi,

I am trying to build my first interactive with Openframeworks, I am an experienced actionscript programmer, but looking to add Openframeworks as a new tool in my toolbox.
In the interactive I have a “pile” of planeprimitives on top of each other, each of them is rotated and scaled.
I want the user to be able to pick one of the planes and by that trigger something.
I have tried to look into ofxRay to use raycast to get the planes under the mouse, but I couldn’t get it to work.
I have also been thinking about using some color-picking to use in buffer with color representations of each plane.
can any of you give me hints in directions of addons or tutorials that might be push me in the right direction that would be best for a beginner to solve this problem.

thank you for your help, Per

maybe this addon can help: