[CRASH] LoL Mac launcher unable to update (Crash at 33%)

I have Mac mini (OS X 10.10.1) Launcher 0.5.0.198 and tried update to patch 4.21, but after process reaching 33% it crashed. Every time! Tried with no luck:

• Restart Mac
• Download fresh launcher

SOLUTION:

1. Start LoL Launcher
2. (Optional) Change region and restart launcher
3. Open Activity Monitor
4. Kill not responding UserKernel process with LoL logo
5. And magically it will update