I will have to dissapoint Illuminator (and maybe opus too), but setting UserControls' BackStyle to transparent will HIDE EVERYTHING there is on that control. Believe me, I tried it.

If you go this way, you must draw shapes on the usercontrol, then set the Image to MaskPicture (MaskPicture = Image)

Or if you don't want to use (don't need) transparent backgrounds simply leave the BackStyle setting to Opaque.
As simple as it gets