Hi
You are not responsible at all. If you notice the lines are not right by all means try to help out. I have in the past had some awkward launches because of seaweed tangling the lines and the launcher has been good enough to warn me.
Personal grip for me when I am launching someone... If you must lay your lines out up-wind of your kite. Walk to the edge of the window before trying to launch. I hate people who try and make me launch them when the kite is fully powered and knocking you over. I have a good mind to hot launch you next time.
