How does button click processing work on a map image up in a window?

How does button click processing work on a map image up in a window? I've tried to add onDoublClick to the lowest level of imagecontrol with the function added into image.lua (can tell its calling my version due to print in onDrop for testing) and it never triggers it. So I looked higher up the chain in manger_image.lua and overrode onImageInit to keep calling the super original code but then replaced the imagecontrol's onDoubleClick with my own - called it directly after to make sure it worked. It did. But was never triggered.

Something is eating the onDoubleClick before it ever reaches imagecontrol but I can't find out what. I have a strong suspicions the window that holds the imagecontrol is somehow eating the clicks and not passing them down into it - even though I can find no code consuming those for that window or see any action if I double click on the open area of an imagecontrol.

I could use some help on what is eating these so I get a chance to do things when they occur.

The image control in FGU is a very specialized control that is doing a lot of things. It does not support the standard mouse event system; since it has to handle a lot of different modes depending on the state of the image data control linked to it.

Regards,
JPG