rough traversing and stalling only in main screen

[Jonathan]

250mm/s^2 is very low for the acceleration. If you leave it at that then the feedrate when cutting parts with lots of small moves will be severly compromised, so I'd try about 1000mm/s^2. Due to using 20mm ballscrews and large pulleys, the inertia of the X-axis is substantially greater than it could have been, which will limit the acceleration you can get, so you may have to reduce the maximum feedrate from 9000mm/min to keep it stable. You could compensate by running that motor on 75V instead of 50V, since at the highest speeds that will get approximately 50% more torque from the motor. Once you've found settings that seem to work, you could try running random G-code from this spreadsheet to test it properly.