Quick DXF to G-Code Conversion Instructions
Under Coordinates, set all start at and Z values to 0, G1 feed Z-direction 150, G1 feed xy direction - 10. This works well for 1/2" steel plate.
Under File Beg. & End - change G21 to G20 for inch units.
Import DXF, then export G-Code.
Keep your DXF in the (x,y) > (0,0) coordinate quadrant.
Download vanngcode.py converter script as discussed in DXF_to_G-code_Conversion_Tutorial
Run conversion, then use the corrected g code file in LinuxCNC CAM software.