Well, in my opinion, you can't use the editors without knowing some xml, or at least how the basic game data xml files are  working, ie. how data is defined within the xml.

For this, you only need a good texteditor to explore the fundamentals of the game xml you want to alter or mod.

A good, small and easy to use universal text editor is proton. I always keep this one on my usb pen drive.

A good source of knowledge that will guide you through the basics is our i-mod xml reference project.

Xml is not hard to understand, and you'll soon write some new lines.

Once you finished your learning process, you are able to use the eg techtree editor.

Basically besides the campaign and scenarioeditor any other editor in the tools folder is just a user interface which writes the xml code for you, however then you are already able to write it by hand.

The editors are just helpers, but sometimes you are even quicker writing some xml lines by hand.

Its really not difficult. Just give it a try before you use the editor, and very quickly you efforts be honored with a working mod.