STUI will look in two separate "STUIAdditions" directories for user scripts and extra STUI window code. One of these is for your private additions, the other is for additions shared with other users on the computer. Both STUIAdditions directories are optional, and you must create them (either one or both) if you want them. You may need special permissions to create the shared directory. The path to each is shown in the About STUI window (as well as whether the directory was found).
Scripts should be put in a directory named Scripts in the STUIAdditions directory; they will then show up immediately in the Scripts menu (you do not have to restart STUI).. For more information see Where To Put Scripts in the Scripting Manual.
Code to generate additional STUI windows can be put directly in a STUIAdditions directory. You will have to restart STUI to make these available. Writing such additions is described in the Programming guide.
In general, additions present in the user STUIAdditions directory mask identically named additions in the shared STUIAdditions directory, and both mask identically named built-in scripts and windows. Thus you should be a bit careful in naming additions. This is discussed in more detail in the scripting and programming manuals.
