Only half axis mapped

Hey guys! I need to map two axis from pedals (Clutch and Throttle) to one axis to use as rudder in aviasimulator DCS World. I've downloaded the vJoy and UCR (Joystick Gremlin too) and with the help of UCR I've merged two axes into one. But when I was testing my new virtual device in Windows Game controller properties it looks like only half an axis is mapped. So to describe the problem better - if we presume that all the axis length is from 0 - 100 and to use it as rudder I need it's neutral position (start position) to be at 50. So when using left pedal the axis would "fill" from 50 to 0. And when using the right pedal the axis would be "filled" from 50 to 100. And here is the problem, my Virtual controller has it's center (neutral, start point) mapped in 25 and left pedal is from 25 - 0, and right is from 25 - 50. So in game I have my tail always turned left, and only when I fully depress my right pedal it stands in center position. Is there any way to fix this? If anybody has any experience or at least guess where could be the problem - please let me know, I'd be very grateful of any help. Thank you guys in advance.

p.s. Also, am I getting it right that the latest version of vJoy is dated 2019?