Make controls transparent in user created forms

Would it be possible to add the following small feature in a future release?

Could we have the option to make listboxes, textboxes and drop down lists etc in user created forms transparent?

I have some quite complex forms which I would like to divide visually by putting the above mentioned objects of top of a JPEG colour wash

That is not easy to do in Windows with standard controls (especially with resizing enabled), and I don't think would be used by many people, so it's unlikely. Sorry.

Group boxes and separators are an alternative. Tab controls with only one tab can also be used for a more visual grouping of controls, since the inside gets a different background color.