Hi,
Those are symptoms of the motors being tuned to run too fast or too high acceleration. Go to the motor tuning pages and reduce the max speed and acceleration to 50% of current setting- When Rapid Feedrate is at 100% (when it moves to first coordinates) it can sometimes skip and jump along it's way and vibrate.
- The stutter is not totally confined to a change of direction. It sometimes happens in the middle of a linear move.
and try running the tool path again.
Craig