Oval Holes

[JAZZCNC]

I have ordered an extension so I can connect to the com port on the drivers (LCD A86Hs). Is there anyone familiar with these settings or had issues such as this before? Jazz, I know you use Lichuans, have you ever had to tune the drivers for such errors?

Yes, I use Lichuan closed-loop Steppers all the time, I buy them by the 100's and can honestly say I've never had any issues. However, don't confuse Closed-loop steppers with servos, they work very differently.
The Following errors described in the example you have given you won't get with a Closed-loop stepper system because they don't work like Servo's where the drive and motor work closely together for positional rotor accuracy and stability. Yes the encoder on the closed-loop stepper system checks for the position but the drive doesn't need this feedback to get into or maintain a stable position like a Servo drive does as it's still a stepping motor and just moves a set amount of steps, it's more of a positional check and then correct or fault if the error is too large.

If you don't have slop/flex or back-lash then I would look more to the motor tuning, the usual culprit is too low acceleration.