Well just to warn you ahead of time, there may be problems with that. If it is glued on and is crooked, this probably wont help much. It will instead just make the entire gantry wobble even more as it tries to keep the rod straight. That is the reason I designed it the way I did and said it works best with another coupling/flexible coupling. Your best bet would be to make some kind of floating nut, to allow the nut to move all over the place but not push the gantry side to side.
With that being said, if you would still like to try I would be happy to upload another file type. Just let me know what extension would work best for importing into openscad!