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Netlist Extraction Short

I have two fat traces on the Gnd plane that show up in the netlist as grounds, net 19. They are not meant to be and in the actual PCB itself they are not. Did I define my layers improperly?
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Thanks for sending the sample file.  After careful review it appears the cause of the Netlist extraction short is the way the clearances for those two traces on the GND layer are constructed.

Instead of a single boundary for each clearance; each clearance consists of multiple adjacent trapezoids.  The netlist engine appears to be confused because each of those internal trapezoids (supposed to be copper) are not fully contained inside the outer trapezoids (i.e. at least 2 sides of each inner trapezoid touch or even overlap the outer trapezoids). 

When turning fill off (menu: View / Fill / None) you can see how difficult it is to figure out what is what because there are so many multiple polygons/trapezoids overlapping each other:

The netlist engine believes those internal dark trapezoids are not fully contained within your outer trapezoids, thus a short is created.

The FIX: By just creating a single outer polygon for each clearance on your GND layer and making sure the traces fit inside my clearance polygon, resolved the issue.  See image and attached workspace:
Please keep in mind simplifying the geometries used in a design with drastically improve analysis results (and even conversion results to other formats). 

Best regards,
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