Not sure what you are making?
Some models do not have material left around the centerline, those are a problem.
One thing you can do is model up a small cylinder, say 6mm in diameter and see if that surface shows through on your model. That will tell you a lot about where your model is in relation to the centerline of the rotary.
Other than that, you might want to post a screen capture of what your model looks like. BTW, what is your toolpath preview showing you?
"If you see a good fight, get in it." Dr. Vernon Jones