Hi Moniack and welcome
We don't use the Viscount in freighter config at CBFSVA but what you
can do is cheat (I hate that word but it fits). Make all the pax stations zero in the aircraft.cfg and look for the line 'empty_weight_CG_position ='. Note what the detail is for this line then add a new station using the same detail and call it Cargo (or whatever comes to mind). Here's an example for the Avro Lancastrian..
[WEIGHT_AND_BALANCE]
max_gross_weight =65000.0
empty_weight =30453.00000 //37200.00000
reference_datum_position = 0.0, 0.0, 0.0
empty_weight_CG_position = 9.630, 0.000, -1.000 (this is the line to look for)
CG_forward_limit = 0
CG_aft_limit = 1
max_number_of_stations =22
empty_weight_pitch_MOI =280130.00000
empty_weight_roll_MOI =226967.00000
empty_weight_yaw_MOI =471760.00000
empty_weight_coupled_MOI =0.00000
station_load.0= 000, 35.000, 0.000, -2.000, Nose_Bags
station_load.1= 200, 29.500, 2.000, 3.000, Pilot
station_load.2= 200, 29.500, -2.000, 3.000, Co-pilot
station_load.3= 200, 27.900, 2.000, 3.000, Nav
station_load.4= 200, 27.900, -2.000, 3.000, Flt_Eng
station_load.5= 550, 30.500, 0.000, -4.500, Fwd_Bagage
station_load.6= 200, 26.900, -3.000, 0.000, Crew_Galley
station_load.7= 200, 26.900, 3.000, 0.000, Crew_Elsan
station_load.8= 180, -2.500, -3.000, 0.000, Seat_1A
station_load.9= 180, -2.500, 3.000, 0.000, Seat_1B
station_load.10= 180, -5.500, -3.000, 0.000, Seat_2A
station_load.11= 180, -5.500, 3.000, 0.000, Seat_2B
station_load.12= 180, -8.500, -3.000, 0.000, Seat_3A
station_load.13= 180, -8.500, 3.000, 0.000, Seat_3B
station_load.14= 180, -11.500, -3.000, 0.000, Seat_4A
station_load.15= 180, -11.500, 3.000, 0.000, Seat_4B
station_load.16= 180, -14.500, -3.000, 0.000, Seat_5
station_load.17= 180, -14.500, 3.000, -0.500, Stewardess
station_load.18= 300, -17.500, -3.000, -0.500, Pax_Galley
station_load.19= 300, -17.500, 3.000, -0.500, Pax_Elsan
station_load.20= 300, -17.500, 0.000, -3.500, Rear_Bags
station_load.21= 7332, 9.630, 0.000, -1.000, Cargo (this is the line I added to the config to enable the Lancastrian to be correctly flown at maximum weight)
It's a dirty fix but lets you load up with the freight centred on the CG.. if that makes sense
EDIT.. I've just had a look at my Viscounts and it seems I have an unholy cocktail (a mixture of old and new). Empty Weight CG Position is listed as all zeros which doesn't help the cause at all

Fraser did the station loads for the latest releases so perhaps he can suggest something more meaningful
ATB
DaveB
