MLCAD is a program for building with LEGOs, akin to the computer game LEGO Creator. It was originally designed in 1999, by Michael Lachmann, and is continually updated to include more advanced features.
MLCAD (Mike's LEGO Computer Aided Design) is a powerful, yet easy to use virtual modeling program designed specifically for use with LEGO parts.
MLCAD is available for Windows and Linux (Mac users see Bricksmith or Mac Brick CAD), and includes support for English, German, Italian, Dutch, Japanese, Czech, French, and Spanish.
MLCAD download and installation - Download the zipped file containing the latest version of MLCAD from this page and unzip it into the LDraw root directory (any place will do, but this is the recommended location).
This tutorial is based on MLCad 3.11, takes for granted that the program is running smoothly and that you are a little familiar with it.
Open the LDraw file Dumper.ldr in MLCad and zoom in 'til the rear of the dumper is well visible in the panes.
To take advantage of MLCad's behavior, which sets the rotation point of the first selected part as rotation point for the rest of the selection, you have to select the helper part first.