NOTE: Demo plugins are about to be saved with this project!
What should I do now?
Continue and save the project, but next time you open it demo plugin/s will be replaced with place holders (don't re-save a project opened in this state, you will lose the original data). You can purchase demo plugins at a later date and the project will open correctly with plugins intact. Alternatively, change the demo plugins to another non-demo plugins prior to saving.
Note: Demo plugins have the word (demo), after the plugin name along top of the window holding the plugin.