However, both the methods described here replace the widget with a background image. For instance, using Fl_Text_Editor or Fl_Help_View and setting text->image() or view->image() will only render the background.

The behavior I want, is for a background image to be set for say, Fl_Help_View and then the contents of the buffer() to be rendered **on top** of the background image.

So, for instance you will have a text editor window with a custom background, and you can style type in the letters.