Yes, is it is pretty user friendly (I'd skip reading the topic, actually, and just check from the end if you have problems). After you download the editor, you just need to unzip it somewhere and run it. It should find your profiles automatically IIRC, but you might need to click on the folder icon and browse to the '..\SteamApps\common\Divinity - Original Sin\Data' folder (or similarly for the GOG version), if it doesn't find the game. There is a folder icon if you need to browse to the My Documents PlayerProfiles folder, as well (c:\users\UserName\Documents\Larian Studios\Divinity Original Sin\PlayerProfiles).
Once it is configured, you just select a save from the list and click on the Load button. That will add tabs for each of the characters (the main characters and original companions will list the names; tabs for Wolgraff or Bairdotr will be blank).
When you switch to a character's tab, you'll get an interface similar to the in-game inventory, and you can add items to the inventory, edit equipment, add/change attribute/ability points, etc.
