It's been ages since I used my Tormach, and I needed to make a half pocket on some mild steel (making a clamp knurling tool for my lathe).
First I updated PP to 2.5.2.
I had no end of trouble making the X-Y make sense. I wanted the center of the pocket to be right through the center of the 1/2" end mill, but by trial and error I found that I needed a half endmill sized offset in X only. Should I have expected this? X=-0.25, y=0 centers the pocket on the endmill?
Also, really wish there was a "goto x,y=0,0 button on the pathpilot screen that would be quite handy from time to time.