I'm really new to CNC having just finished a 1.5 year CNC build. Now I'm working through learning G-code generation. I'm using FreeCad to create text using a pocket. I get an error when I load up the Gcode in PlanetCNC software; K word given for arc in xy plane. I'm using the grbl processor option in FreeCad. It works fine when I create pockets using straight lines or when engraving. Is there a processor that is specific to PlanetCNC software? Any ideas how this error is occurring? Thank you.

Kurt