I downloaded BNSF 8-40b #8603,<kuid2:113556:60077:3> which used the kuid2:9000:51013:1 enginespec. After cleaning up about 50 texture errors I tried driving it. CAB mode worked ok, max speed 80 mph. DCC mode however was a lead sled. Edited the enginespec to change max speed from 33 to 36 meters/sec (equivalent to 80 mph) and changed the max-accel value from 1500 to 50000. DCC drives similar to CAB now.
What loco are you using kuid2:9000:51013:1 on?
Bob