As with all steam locomotives, driving the 232 U requires a little instruction.
We only deal here with the "realistic" mode
At start-up :
push the 'stocker' lever all the way in
note the pressure in the boiler
release the brakes and wait for the pressure in the brake cylinders to drop to zero
push the regulator to the maximum
Gradually increase the steam supply to the cylinders by turning the Cut Off to the right (forward) or to the left (reverse)