Custom Mover
UT has several subclasses of Mover that did various things. UT2003 has just the Mover class.
It's possible to script custom movers in UnrealEd 3, just as it was in UnrealEd 2. Whether they are actually required or not – that's another question: watch this space! 
Creating
You need to write a script yourself, compile it and put it in the ini file as an EditPackage (same as custom brushbuilders).
To add a mover of a custom class:
- select a static mesh resource in the browser
- right-click the mover toolbox button
- select the class
Scripts
this would be a good place to post scripts...
Related Topics
Discussion
SuperApe: Perhaps this needs a to be merged with Scripting Movers?
