Unintended motor movement in open loop

I've managed to get my machine running fairly well. However, when I try to turn up the speed a bit, I get a few different problems (different ones on different axes). On one axis(A) I get what looks like a following error, where the drive accelerates up to its final location, and then has to back off to get to the commanded position. On other drives, I get an odd issue where the motion produced by the G0 code doesn't end before an M64 command, causing motion to continue after an air cylinder has been triggered. The g-code problem might be isolated, but the excess movement problem isn't.

I have tried setting different values for FERROR and MIN_FERROR (from 0.0005 to 1), as well as velocity (0.33 all the way up to 2), and acceleration (0.33 all the way up to 20). One item that may help in the diagnosis is that the drives do stop quickly when they reach the MAX_LIMIT and MIN_LIMIT locations.

I am running a set of 4 servos with the encoders handled by the drives - so LinuxCNC doesn't have any encoder input (open loop). Otherwise I would have said it was a PID/FFn problem.

For those that are curious, my configuration files and G-code are attached. They should be functional, but the g-code isn't complete yet.

Thanks in advance!

Looks like the machine acceleration and velocity limits are set higher
than the stepgen limits so as soon as you accelerate faster or move
faster than the stepgen the stepgen gets behind

The stepgen velocity and acceleration limits need to be about 1.25 X the machine limits

Excellent. An easy fix - the whole setup works like a charm now.