hey guys, when i start the downloader it says error creating installation directory. plz help

Make sure you are not trying to install into programs files, also make sure your antivirus is not blocking the installition client.
another method that might work
Step 1: Uninstall Pando. If it's not in add/remove programs list, go to Program Files > Pando Networks > Media Booster > uninst.exe

Step 2: Download and install this: cdn.pandonetworks.com/pando/pmb/PMBInst.exe
Step 3: Download LeagueofLegends.exe from https://signup.leagueoflegends.com/en/signup/redownload
Step 4: Place file in a folder on the desktop named "League of Legends"
Step 5: Run the file as administrator