I also had to get the bike shop with impact gun to loosen the factory installed cs nut. Since then I used a breaker bar and a padlock thru the rear sprocket and chain to stop the cs turning.
49 or 50 rear sprockets with 13 for off road or 14 for dual purpose rides.
Tried a MT43 trials tyre earlier this year, had great traction but it raised the bike seat too high and the gearing was equivalent to +1 on cs. 114 link chain to clear mudflap with 13/50 sprockets for a dual purpose ride.
Have just sold my WRR and am questioning that decision