Could you please post a screenshot of your filesystem to show exactly where you have put the group?
Could you as well post the full group permission file here for me to see just in case there is a mistake in it?
And last could you post a log file for me to see if the group is being loaded or not? If you are running a server then the log should be there already in the Logs folder. If you are trying out the groups on your client then you need to enable the debug console for a log to be generated, to do that do the following:
Open the config.properties file, found in the RW directory, with a text editor and change the value "game_debug_console=false" to "true".
After start the game enter to your world wait a few seconds and close the game and upload the log here.