The control software can "re-align" the part when it is rotated. For example, when you rotate 90 degrees, and you tell the machine to move in "X", the machine "Y" axis will physically move. And more complex if you have odd angles. The basic idea is that you program x and y as it is shown on the print and the machine will rotate and do everything else for you.
The m128 is for simultaneous 5 axis work where the tool tip follows the part during rotation.
the salesman will have a better description when you talk with him/her.