We've been working to make the standalone editor more consistent when used with Questlists and nudges. Now, when using the standalone editor, nudges and Questlists won't show up unless they are previewed.
To get a nudge or a Questlist to preview, head into the "Nudges" or "Questlists" tab and click on the nudge or Questlist you want to preview. Then, it'll show up.
This reduces clutter in the editor and makes it easier to focus on the widget you're trying to edit.