1. Extract content in downloaded rar file.
2. Make a back up of your original fles
3. Open your PKCMN.pak file with win rar
   Located under the directory where you installed your game Normaly c:\program files\steam\steamapps\common\rugby Challenge 3
4. Double click on environments directory
5. Double click on Pops directory
6. Double click on posts_generic directory
7. Click on the add button 
8. Select the down loaded file and press ok
9. Close all