League doesn't allow to change client theme with older version

Can someone tell me how to change my Client theme with older one (17th of July , 2013 - Spirit Guard Udyr ) ? I want to change my client starting theme and when I do it with Lol Replay 2 .. League client says: We have restored the installation of an older version of League of Legends . Now we'll restart to try to install latest version ! - and restarts my client and then the latest theme - FUCkin.g poppy appears on my screen . FFS is it so much to want a cool theme on my starting client ? ... Is there a Way I can stop the restart of the latest version and play with Udyr client theme ?