I've been using the League of Legends setup script via PlayOnLinux, because it's the only way I can get it working.
The setup went well, and so did the client update.
The only problem is that when I try to login, it tells me that my login info is wrong.
I think that this happens because PoL downloads the LoL files for europe-west or usa, but I couldn't find a way to download the files for europe-east, which is the server I need. Even if I choose to give it manually the LeagueOfLegends.tar file, I couldn't find one that is specific for East Europe.