I am using it to generate files for a DT2200 Plotter/Cutter however although the sizes are correct in Librecad once they have been saved as a DXF file and uploaded to the cutter the dimensions have massively increased (eg a 1888mm line becomes over 47k mm long).
I have checked the units are properly set as mm and also my general ratio is 1.
So it looks like it is a mm vs inches problem. Maybe the plotter expects inches as input and you have to adjust something with the plotter. Or, if there is no way for this, you may rescale your drawing to inches.