[tantemay]

In which programming language are the Planet-CNC scripts written?
Are they also scribed like Mach3 in Microsoft Virtual Basic?

Unfortunately, I can not find anything else about the scripts. The Planet CNC TNG developer says on every occasion how great everything is, but that's about it.

[PlanetCNC]

Script is g-code. There are three main ways to use this.
1. Change behaviour of program commands. For example, g-code under menu "Machine/Move/Move to zero" is G00 X0Y0Z0... On some machines it is practical to move Z axis first which is easy because of this feature.
2. You can create your own procedures. Usually used for g-code generators or custom measuring routines.
3. Override M code behaviour. You can easy add delay to M3 spindle or implement tool changer specifics on M6.

It is not needed to use scripts. They are for advanced users that need support for specific hardware needs or for custom prodedures.