AndreasR thank you very much for the compliment!
In C2 there are two types of objects, objects drawn on canvas and HTML objects.
HTML objects work independently of canvas, they do not interact directly. It is not possible to place a layer over an HTML object. The layer only works for objects drawn on the canvas.
**objects in Form Controls are HTML objects.
Unfortunately this is not possible for this plugin or any other HTML object.
Cheers.