After some difficulties with the custom office in Germany I finally got my BombiniBot-Kit today.Assembling the bot was quite easy, however the instruction could be more detailled in some steps.What disturbs me most: the bot is not able to drive straight ahead. It turns right - and not an insignificant amount either. This is because the motors are very different. You can feel the difference by turning the tires. I expected more precision in this detail as it is dedicated to teach children (the younger ones!) somethng about robotics - and you surely don't want to start teaching them a p_controller just for driving straight ahead. Any idea how to fix?