It sounds like the MX5500 isn't recongnising the stand. There is a sequence to follow when attaching a motorised stand to a MX for it to recognise it and hopefully this is the problem.
Unplug the TV from the mains & detach the stand connection. Then plug the stand into the TV before plugging the TV back into the mains & powering on,
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Chris.
The use of metaphors should be avoided like the plague. They're like a red rag to a bull to me.