If a vision label component created and and the background colour is set to something other than that of the page background, selecting Fill Background = False has no effect, the background is still visible.
If you just create the label and do not deliberately set a background colour, it will by default take the page background colour, if you then change the page back round colour the label background changes with it, giving the illusion of transparency, but this is not much use if the label is over a gradient or some other graphic.
Paul,
If it would be of any help I have a small example project I could send over, it demonstrates the transparency issue and other likely related issues?