Is there a plugin demo we can try?

Are you asking about a demo of the bbPress Voting Pro plugin? You can see that in action in my own forum at https://wpforthewin.com/forums/ (although not much content in it yet)

If you’re not referring to the pro plugin, the free version is available to download from the WordPress plugin directory. You’re free to try it out and consider upgrading to the pro version to get the extra features.