There is a bug in jit.mxform2d.maxhelp (Max7.0.6 and earlier). The order of float numbers connected to the pak object is wrong, it should be, a c tx, b d ty then u v w. Instead of current.
When mxform list is sent in this proper order, the object will work as homographic transformer with 3x3 matrix input, can be used to remove distortion from 2D image, etc. The matrix can be calculated in various ways, easiest is to use cv.jit.findhomography or cv.jit.getperspective.
(please list things that you believe to be errors or omissions from the existing refpage)