@xaxjon I can help with 2 of those:
(3) The ident button not working is a msfs limitation. There's no way (I believe) for the PE client to know when the button is pressed.
(6) Re your last point, on the EFB, make sure auto fuel selector is off. In case you are unaware, to show the EFB use the I/COMM switch next to the DME source switch.