Normally there is 3 wires from the rx to fcb, 5v ground & signal. These 3 wires
Carry the power & data to & from.
That white wire is not coming from the usual pins that carry voltage & signal.
I could be wrong but. You need to do some basic research on the components you are using & what goes where.
I just googled the pdf for your rx and you are getting the S port mixed up with sbus.
So forget about the white for now & use the red, black and yellow. You already got the power wires hooked so just put the yellow on either sbus or ppm. So providing your Tx is bound to rx, all you have to do now is the ports tab.
Select soft serial & match the baud rate if it needs changing. Also I think on the configuration tab is a box that needs ticking to use soft serial.
When my Tx came it was not set up for what I use so maybe you have to change something, so it can use the sbus.
Try the ppm set-up first. It's easier.
No soft serial is needed the fcb should pick it up even if you have soft serial on.