moulding toolpath help

[bobmoore]

I am using the moulding toolpath for the first time and having an issue. I am routing my 3 inch tall by 6 inch wide board with a 5/8 core box bit with a 2 inch radius above a 1 inch flat. The program looks correct to me but the resulting radius is about .3 inches above where I want it. I have tried zeroing to the top of the part and to the table with the same effect. I can actually see it in the preview mode but can't get it to work correctly without cheating. Must be something basic but I am stuck. Thanks
Bob