[Plugin: Super Post and Page Widget] The plugin makes another sidebar not working

Hi!
The plugin seams to work properly but it affect other stuff in the webpage where I insert it (you can see i.e. at https://www.freereporter.info/wordpress/2012/03/16/widget/).
The plugin affect the sidebar n°2 (the one on the right) preventing it to execute or to run some widget. In pages where I don’t use your plugin the sidebar n°2 works properly (i.e. here).
How to fix this problem?
Thank you very much…. the plugin would be really useful!
Rocco

https://www.ads-software.com/extend/plugins/super-post-and-page-plugin/