You mention you are trying to use the demo. It could be the demo was created with a different IDE version than yours. Have you tried the "Revert System Files to Default" option? Don't forget you'll need to add the necessary JAR files after doing that.
To add the JAR files, you can follow this guide:
Alternatively to track down this issue: does this also happen if you drop the component in a new project and add the necessary JAR files to the project? Do you see any error messages?
