The KMotionCNC GCode Interpreter can perform Rigid Tapping by invoking a C Program in KFLOP that performs the necessary synchronized motions.
At this time this is under development and is provided as a Patch to Test Version 4.33h34h. The Patch DLL (and source changes), C Program Example, and GCode Example are located here:
[http://dynomotion.com/Software/Patch/AddG84RigidTapV433hAddG84RigidTapV434h/ http://dynomotion.com/Software/Patch/AddG84RigidTapV433hAddG84RigidTapV434h/]