Angle X, Y, Z: Controls the amounts that the selected points are twisted around the axes. Use the ControlChannels to control how the twist amplitude is distributed along each axis.
OK: Closes the tool, with alterations intact..
Cancel: Closes the tool, canceling any alterations.
Set: Makes any alterations permanent, and leaves the tool open, ready for further use.
The Twist tool also includes a standard Origin Tab, allowing you to set the Origin around which the tool twists points.