As noted in my preceding post:
"I decided to try very quickly activating the direction button on my handheld -- or the direction slider on the ZW-L -- and that worked great for easily changing the direction. I hope that procedure continues to work...."
Unfortunately, instead, the direction control using the hand held remote, or, the transformer direction slider, no longer sequences the direction, and the locomotive is currently stuck in neutral. The locomotive does sound beautiful though! She may become "the star of the siding" until I am able to figure this out!