There seems to be a lot of confusion around the context in which word "transparent" applies to an imgCanvas (using gdiPlusX).
It seems that the transparency means "the amount of the previously rendered pixels on the canvas that will seep through any new drawing on that same canvas". I need the canvas itself to be transparent, so I can have two or three canvases overlaid, made visible/invisible at will, and if need be, show some VFP controls beneath them (maybe a label or a background shape, nothing clickable, of course).
After googling this for hours, I'm at the end of my wits.