We in North America do not get Sequentronic, so I can't comment with certainty about that. I would doubt very much that using it would hurt the transmission. I would expect that there is a processor in the Sequentronic which would not let you do anything foolish. As for normal wear and tear, I can't see how shifting it yourself would cause more wear than leaving it in auto mode. Follow the procedures in the operator's manual and enjoy your car.
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