Which bit of that thread were you referring to?
The final comment (talking about the story-hints window not showing text) is due to a bug in the source, rather than anywhere else. The problem is that it declares a text-buffer window with a height of 1 line, and then proceeds to print three lines (two lines of text and an automatic paragraph break) so it scrolls out of view. It can be fixed by changing to a text grid window and then replacing this rule:
Rule for refreshing the story-hints window:
say "Stuck in the story? [red reverse]Do not dial 911[default letters] in the [highlighted]USA![no line break][default letters] - Try west.[no line break]".
Note explicit suppression of line breaks after the exclamation point – that’s otherwise a location that I7 will helpfully inject one for you because it sees an ending punctuation character followed by a “separate rule”. (I’d be happier if it didn’t do that, but such is life.)
Although actually with this change it will work without using a text grid window, as long as the screen width is wide enough to not trigger word wrapping. Which is good because you need more changes to change the style of a text grid window, since that defaults to reverse.
(The existing glk styles do feel quite restrictive sometimes, though.)
FWIW, the extra change to make the background colour work for the text grid window is to add the “reversed” column to the Table of User Styles, with this extra row:
story-hints all-styles -- -- false