This product is also included in Wall Worm Pro Pack. If you use Wall Worm, you should update WW itself and not use this standalone version.

CorVex is a scripted geometry plugin for 3ds Max 2010+ aimed at quickly building game level layout for any game engine or even general design. It offers convenient planar mapping controls for geometry that is controlled by spline bases. You can create blocks or walls, and the walls have much more convenient UV control than standard AEC Walls.

You can find the full documentation on CorVex here.

Geometry
New Geometry Class	New Geometry class named CorVex in the Create Tab under the Wall Worm category.
UV Controls	UV controls built into the geometry parameters. Control UVs in the modify tab.
Vertex Grid Snapping	Option to force all vertices to snap to the world grid.
Brush Geometry	Creates valid Brushes for Source.
Requirements
Minimum Version of 3ds Max	Probably any version of 3ds Max
Exporters
VMF Exporter Link	Has native options for exporting as a collection of grouped brushes, func_detail and/or as 3D skybox in the Wall Worm and Wall Worm Pro VMF exporter.