The setup described below gives you the maximum possible downward flap movement as requested but does not permit any upward flap movement at all. If you also require some reflex or coupled aileron/flap then you will need to sacrifice some of the downward movement to give you the necessary up movement. You can achieve this by reducing the offset values in Flap Set.
First go to the END POINT MENU screen 2 and set the limit and end points for both FLAP and FLAP2 to their maximum values (155 and 140) in each direction.
Now go to the FLAP SET MENU and set both the OFFSET values at the bottom of the screen to minus 72. This will move the servos to one end of their travel with the throttle stick fully forward.
Next go to the BUTTERFLY MENU. On screen 1 set both FLAP and FLAP2 to their maximum values (200). On screen 3 set the mix from INH to ACT.
At the bottom of Butterfly Screen 3 you will see a % figure in brackets. This indicates the position of the throttle stick. Move the throttle fully forward so that this figure is 0%. Now scroll to the OFFSET value immediately above this and hold RETURN for 1 second. The OFFSET should now be set at 0%. This will give you end to end control across the whole of the stick movement as requested.
A check of the servo monitor will show the two flap servos moving from -152 to +152 in response to the throttle stick.
(courtesy of RCG user MalcolmHolt)