Goflight mcp pro is the piece of hardware, unfortunately goflight does not provide any piece of software to make their hardware work for xplane as they do for fsx. To make it work you need the software/plugin from a third party which interacts between the hardware and the aircraft custom commands datarefs.
i do own the goglight mcp pro and i bought pollypot goflight interface tool https://shop.pollypotsoftware.org.uk/goflight-interface-tool-xplane.html
WORKS BRILLANT rock solid! Not only the IXEG, you are also able to make your MCP PRO to work with any other aircraft you have on your hangar . as well as the other goflight pieces of hardware like te EFIS, etc.
The whole idea how it works is:
-you install the interface software on your xplane machine (windows only!) it auto detects your goflight hardware connected.
-You create/edit a per aircraft profile on a graphical user interface. Profiles are loaded automatically for the aircraft you select on xplane.
-When you create/edit a profile you select what button, display, switch, light on the goflight mcp pro does what on the aircraft. Creating a profile for the IXEG 737 is straight forward because the external mcp matches the aircraft mcp. But the funny part is you can also use the mcp pro for a C172, SAAB340, 777, 757 or any aircraft on your hangar. You just decide what does what as per your liking. The C172 does not have FD switches, but you may leave them off but usee HDG rotary, altitude, speed, course selectors, CMD A to engage A/P etc.
-Profiles are exportable/importable, you can exchange profiles with the community. There are profiles already shared on their forums. I do have created my profiles for the IXEG, SAAB, 727/737FJS, AFL172, FF birds. Once you understand a bit how the interface works it is quite easy to create, fine tune the profiles as per your liking.
hope this clarifies.