I am wondering if they sprayed everything with the spoiler up and got paint dried in the joints of the arms that could be gumming something up at some point and if the spoiler motor detects any type of resistance along the way it probably halts retraction immediately for liability reasons so some little kid's hand couldn't get caught in it while trying to retract. Maybe that is why on manual retraction it goes down in stages instead of smoothly all the way as it is measuring any form of resistance? Maybe try spraying all joints on the arms with some WD40 or better yet, hit them with some penetrating oil. Then try working it with the manual power switch up and down and see if it eventually closes all the way. Just a thought.