Well this would explain my issue. Not really a problem but I created an ellipse (14"x7") using the default ellipse tool in Mastercam X5 and imported the G-code into Mach3. The cut looks good but the bit will move about 1/4" at a time and then pause, then move again. I have cut curved shapes that were created in Mastercam and they cut fine. The ellipse cut looks good but it does create a little extra work smoothing the edges with sandpaper. Not sure how to fix it as I don't know how else to that shape manually. But it is good enough for what I am doing. But this post just solved my curiosity of this.