This script creates a new menu scene - Scene_PokeMenu. You can allow this new scene to overwrite the default menu scene. This script was designed for a 1 actor party. It could be used with more; however, it does not show a status page within the menu scene.
If you call a scene that can display various actors - such as scene status, it will always call actor 1's infomation.
Additionally, you can use this script to easily add new commands for custom scenes you may be using.