With the "replace" function, clicking the text causes the old text to fade out slowly, and the new text to fade in. Is it possible to replace text more quickly?

Hello, this is not possible without change the squiffy's code.

For change more fast the text you find this lines in your story.js and change the value 1000 (1 second) for other value same 200 (0.2seconds) or 500 (half second)

    $labels.fadeOut(1000, function() {
        $labels.html(squiffy.ui.processText(text));
        $labels.fadeIn(1000, function() {
            squiffy.story.save();
        });
    });

Great! Thank you!