I did exactly the same thing,but my "Southwest Limited" ran over the Transcon with the exception of getting into Topeka and Wichita. Anyway,I think that I have reasoned out my problem with the broken couplers. At the switch right before the tunnel,there is a very tight curve[which is where the pull-apart happened]The derailment indicator would come on and then the pull apart,so I guess those cars could not navigate such tight curves. Anyway,I just disabled the "break couplers" feature[it will stay that way!!] and that was that!!! Also,the part that broke away became a runaway back down the grade[shouldn't happen] even with the rear end support. Thanks' for replying.Brian


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