Ah, thank you for the information, Technologicat! 
Hmm… Would it not be simpler to create diffs on a file-by-file basis (as it seems that my diff-tool (Meld) will do), given that I have only three files to patch?
As to DirectRadioButton, this thread was just posted, and prompted the thought: would it be worth further altering DirectRadioButton such that, if “boxImage” is provided and is a tuple of at least two entries, and “boxGeom” isn’t provided, the system assumes that “boxImage” contains depictions of the “on” and “off” states, and thus doesn’t use the default asterisk? Custom indicators could still be used by specifying “boxGeom”.