Icon Packs are icon sets for Notepad X controls, each set have an .xml file and a folder with the same name were the icons are located.
To change the icons open the Icons tab at Options dialog, if you don’t choose any icon set the application wont have any icons at all.
The easier way to create an icon pack is to use the icon pack editor plugin, you can also create the pack manually.
All the available icon names to use are : file, new, open, recent, clear, save, saveas, close, remove, cancel, print, printpreview, pagesetup, exit, edit, undo, redo, copy, cut, paste, find, goto, next, tabs, rename, tools, options, highlight, favourites, linenumbers, help, about, website, bugreport, submitanidea, shortcut, plugins, toolbar, download, documentok, documentchanged, refresh, update, ok, apply, previous, icons, add, replace . The are located as enum at Notepad_X.Classes.Icons
To share the icon packs the application use a custom .pack format, it’s a single file which holds the xml file and the folder with the images. When you download icons pack they are at this .pack format, when the .pack file are found at the Icons Notepad X will extract the pack. You can use the Icon Pack Editor to import .pack files export and edit them.