LoL Screensaver issue

So i'm just trying to change the wallpapers but can't open any sort of program or interface like I used to do I pressed Q (and even A, azerty shenanigans) but this does nothing. So I tried to launch the screensaver app from the directory in C:\RiotGames but when I run "screensaver.exe" in "Browser" two error dialog boxes appear and tells me exactly this : "Unable to start screensaver. Switch --lol-launcher required." and then "C:\LolScreenSaver\browser\screensaver.exe"

I need help !