The size of the program doesn't matter and 20 IPM is actually very slow.
The STOPPED (2) is a message recorded in the History file that indicates an Emergency stop condition. The reason needs to be investigated deeper as to cause. Without investigating or knowing more most likely the increased inertia at higher feedrates created the E-Stop which was caused by excessive position error. Excessive position error could be caused by Tolerance, Blend or other settings but is usually due to servo tuning or motor size.
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