OK when I’m testing my story, I see that I have the option to view the hidden variables. Now for the stupid question — that’s only because I’m the author, right? Someone playing/reading will not have that option?
Correct! For example, I do not have the option to click and see hidden variables when playing Becoming a Warrior or Hopeless Hotties, which I don't own, but do have the option when playing one of my own games.
"Author" might not be completely correct. It should rather be when you have the story role "Owner" (e.g. the creator of the story) or "Editor". Being an author of a chapter or given the story role "Author" shouldn't give you that option if I remember correctly.
