cezary,
dude you just need a little more time on the beach flying your kite and getting used to the whole experience and the way the kite fly's.The Waroos are fantastic kites and are dead set easy to fly once you have the basics down.
Kites are hard to fly in light winds when you are learning,its like driving a car on ice.. every mistake is magnified and its so much easeyer for you to loose controll.
Also there is no need to fold the Leading Edge on moden bow/hybrid kites when self launching. you also mention some other bizzar points.
Sounds like you should go see the boy's at SHQ or RPS and get yourself some decent lessons and re learn the basics.
Good effort for trying on such a light day though,I know how it is when you get new toys and you just want to get out there no matter what.

Flying kites in light winds and keeping them under contoll is one of the best things to do really to understand how it all works.
It can however end in frustration.
You watch next time you go out in slightly stronger winds it will be all to easy for you and you will have learnt some new skills from that last sesh in light winds.
Your next reveiw on the new 2009 Waroo will be nothing but praises!

Enjoy your new kite its a good one, dont worry!
Regards
Luke