All our software tagged as V5 ship with a Lua scripting language that expose new classes and libraries that allow users to extend the existing features or create new one.
If you are new with the Lua scripting language, the Lua Docs and the examples inside this knowledge base are the perfect start.
To write the code you can use the built-in editor or use any text editor of your choice.
Encoding errors might happen on some systems. Select UTF-8 encoding in your favorite IDE.
You should keep most of your scripts functions and variables as local to avoid collision with other scripts. Global variables should only be used to write libraries or scripts that interact with each other.