Run the RuleChager.exe (self-extracting archieve) Type in your Age of Wonders directory (default: C:\Program Files\Triumph Studios\Age Of Wonders)
A shortcut will automatically appear on your desktop. Now you can run the Rule Changer.
By the way: The LordOfMaps' release of Rule Changer didn't work on Win2000 / XP because the choice.exe/com file was missing.
If you're at all apprehensive about installing a mod and having to use DOS to switch back and forth between the standard ruleset and, for example, Warlock's Ruleset, this is for you! It makes it so easy. Plus, it works in VISTA!