This path controls where the client finds scripts and menus. A typical example would be.
SET LOAD_PATH .:~/.irc:/usr/local/lib/irc/script
Which will first look in the current directory, and then in the system's irc script directory. This can of course be set to anything you want. If you want to determine if you have the default scripts, and where they are, use /WHICH global and that should show you the location of the 'global' script file. The directory it's in is also the location of all the other scripts.