Looked like gibberish doesn’t really tell us much. It might have been the way you set up the model in the first place or some setting in the DXF export. If you share the SKP and DXF files so we can see what you started with and what you ended up with, we can give you some guidance.
The DXF export is fully functional in the trial version. As you go forward you will need either SketchUp 2019 or SketchUp SHop to be able to export DXF files.
By the way, plase correct your profile. Currently it shows you are using two different versions of SketchUp and doesn’t show the graphics card.
Just today I learned from Aaron that the 2D and 3D DXF exporters work in different ways. To get the best file for your cutting machine, design the outlines flat on the ground, delete any faces, and export the edges as DXF 3D.