We are using WINCNC. Is there something better?

We have a Warthog CNC router, but the manufacturer's tech support isn't helping us very well. We checked the resolution and backlash compensation, but our cuts are out of the path at at the entry and withdraw points of the lines. A straight line looks like this
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The "out of Round" appears to be one degree and is always on the same side.

Also, parallel lines cut in the same direction are properly spaced. If the lines are cut opposite directions, then they are off by about 1/16th of an inch

My boss insists nothing is loose and the bearings should be good

Please e-mail, also. Thanks!
cnc@archcasings.com