In Yosemite when I press a window's green 'fullsize' button, it will be full size, but somehow differently from earlier way, I can not use change between windows shortcut, because window will claim the whole screen. Any idea how to use it earlier?
You could use a third party app and define a key combination.
I personally use Moom (I am not affiliated with it) and defined cmd+shift+Z
Or you can hover with the mouse on the green button and after a short delay choose the windows layout: