Illustrator :: Unable To Save Brush Created Shapes As DXF?

I'm using Illustrator to creat shapes that can be exported as DXF files then taken into a program used in CNC plasma cutting of metal art. I'm able to do this with art work drawn with the pencil tool and blob brush. I also want to do this with the brush tools creating florishes and other shapes. I've been able to take a paint brush drawn line with width, rasterized it,  and then image traced it to creat a line shape with handles which allow it to be adjusted however I've not been able to get rid of the selection box, it seems to need to be selected in order to work on the shape, and the drawn lines created when I image traced it seem to be double lines. Also I can't get rid of the box that is drawn when I select the lines so I can use the handles to manipulate the shape. Most important I've not be able to export shapes draw this way as a DXF file.