The only way tp get a 2D gauge to pop up on a 2D panel by clicking on it is to make the gauge clickable, this is done by adding a mouse clickable area to the gauge & this is done by editing the gauge xml file, then the panel.cfg will need entries for each pop up window. If you are happy to have a go at doing this, I would be happy to show you in more detail how to do this & help you through it.