Perhaps I didn't understand what you are looking for....
AS I'm now not sure what you want to be able to do, here is an overview what the MachStdMill package can do:
MachStdMill can use a probe to find vertical, horizontal and angled surfaces. it will also find centers of rectangular and circular pockets and extrusions; measure width of valleys & ridges, find cylinder diameters from the side etc.
While the probe operations are intended for job setup etc., the operations report the coordinates and sizes of things found by the probing operations. For simple reverse engineering, there is a button in the software called "probe only" - this allows you to use the operations to find part features - but not move WC zeros etc. The combination makes it relatively easy to probe to locations & dimensions of part features etc.
While the facility was not targeted to do CMM type of operations, it will let you use mach to do simple CMM like things.
Dave