[Burningsoul]

I believe (it's been a few years) those are just presets labled as an .ini or .txt file somewhere in the program's directory tree - you could just open them up and add/replace the itemID's. You'd still have to look up the proper ItemIDs to put in it mind you, so it's not 1-click solution.

EDIT: Just checked, assuming you're using the loot_editor_randomizer tool, the lists subfolder has what you're looking for.