O, thanks for answer from first-hand. I spend two hours trying to debug it and to figure out what i'm doing wrong and what is the logic behind such behavior. At last I move code from gsap.defaults - and all works! Defaults with modifiers used because all tweens in timeline will be using two ways, and second way is mirror the first around center. It's for slider prev and next animation. Perhaps, as always, there are many other ways to do this, but i'm only few day with greensock and watch tutorial where use this way.
It will be great if you provide more info about x/yPercent, because short info from greensock on this topics is not enough for me, after some experiments around it I assume I received some basic understanding what is going on under the hood, but I want to check is it correct, so any further info will be very helpfull.
Thanks in advance