Themeing Shortcode Carousel plugin?

I'd like to change the way the carousel displays--specifically to use fullsize instead of square_thumbnail.

I've tried copying carousel.php into my theme in folders named shortcode-carousel, shortcodecarousel, and shortcodecarousel/public. I added a random "test test test" div to be sure, and in every case, the plugin still shows the default view.

How do we change the display beyond the parameters offered in the shortcode itself?

Since the shortcode just returns HTML to replace on the simple page, it doesn't go through the usual routing pattern for views. So, sadly, it looks like that leaves you with directly changing the code. But, making that an additional config option is probably a good idea.