I have been using this for over a year now, on my 4 x 8 cnc router.

https://app.box.com/s/rromi7wdt90htb0jx66b

just save / place the post processor file "IMSIDesign/TCWP21/CAM/CodeSystems" folder, where TCWP21 -"21" is the version of TC you are running.