Linuxcnc motion backwards (adaptive-feed negative value) and nothing happens

This page outlines the process but I am not the one to ask for help.
linuxcnc.org/docs/html/code/contributing-to-linuxcnc.html

@Rodw,

Thank you for your link, that's the good page to investegate for me.
Last day's i made big step's. Linuxcnc is just as learning a new language.

Coming time i must make time for integrating dxf converters and external program's (python code) into the main program.
So this sound easy, but it's hard to understand how to.

I think to start with the simple dxf2gcode example on youtube. Help is welcome!! to integrate this on a simple way.
But maybe change the source code, because of the way it's written. I looked at it. you can't change it in glade.