I finnaly ended seting w3tc config up. It did turn the site a lot faster, but also made it damn ugly, seeming like an old old html file from the late 90´s. Anyone has the least clue why did it happened? I won´t give my url here, cause I can´t let my site that ugly for a long time, it has lots of users.
So, unless i can´t get that cleared, it will be impossible to use w3tc plugin.