I don't think there is a tut on that, there's tuts that say what each function does (although most aren't complete and outdated now with the addition of linked transforms and xaos). A script just does for you what you do manually in the editor, example from a script would be "Clear;", in the editor that would be clicking the new blank flame button, "AddTransform;" would be like you added a new transform in the editor, then you would change the variations/variables/color, etc. A batch script allows you to create a batch of flames that either overlay on existing flames (there would be no "Clear;" line in the script) or as a batch that are random flames based on the options the script does, if there are no random options it would recreate the same flame every time
(that's what the "generate script from flame" does but that function is often buggy, like not getting pitch/yaw etc. values). Mainly I wrote my scripts for a friend who has epilepsy and had a hard time setting up the basic forms in the editor