Error 50 while integrating drivers

DISM does not support servicing a Windows Vista RTM or earlier operating system.
If the operating system is supported check that SSShim.DLL is present.

I've checked SSShim.dll is present

Solved!

Hey rivurrb.
Do you care to share please..??

Regards.
RoyM

After you copy the drivers to the folder there's a blue "play" button right next to the "Copy Drivers Here", you dont actually need to select it aslong as you have the "Integrate Drivers" checkbox checked.
Just build your Win10XPE and it will integrate them automatically.