Hi There, I face the same problem. Installed the plugin and created a sample button. the shortcode shows and not the button. using wordpress 3.5.2
The default preview short code is coming as [su_https://www.geosai.com.au/wp-content/plugins/shortcodes-ultimate]Button text[/su_https://www.geosai.com.au/wp-content/plugins/shortcodes-ultimate]
changing it manually to su_button sort of works.
