Devo8s rx802 and Gaui 500x Gu-ins

Hi everyone after reading a lot on the forum,
I finally decided to mod my devo8s with the WLToy's v911 transmitter and it works great

But as for my Gaui500X quadra I got the basic setup to work but I have no clue how to set up a switch to switch from manual flight mode to auto balance and GPS
As well as a return home switch
It was working under the normal devo8s firmware but with deviation I can't figure it out

Also after that is set I would love to find a way to move the camera gimbal would it be possible to have a switch that will enable me to control titl and roll control for the gimbal with the two little trims on the two top panels of the remote ?

And lastly does anyone know if I could get telemetry from my gaui500x I know I have it going to my osd but could I have it on the devo8s as well or do I need to get the walkera telemetry module ?

Anyone here could help I would be extremely grateful

Cheers

anyone has any idea

Thanks for replying
Here is the connection schematics of the GUI so you get a better sense of how it is plugged

Thanks a lot ill try it at once

THank you so much everything seems to work fine I had to reverse the ELEV AILE and RUDD channels but all the rest works great

the only thing that doesnt work is the gymbal servo...
it doesnt seem to do anything when I move the trims

Thanks a lot everything seems to work fine
i ll post a video as soon as the wind is down and i can go out and fly