Rinkwraith

Microsoft Store here as well.

Let me know if there's anything you want me to try etc.

P.S. I'm not sure if it makes a difference whether you exit the session with the switch on or off. Just in case that helps test persistent data - I suspect I quit with it off (unless I crash, which is the usual outcome, in which case I'm probably exiting with it set to on.)

I have the same problem. Bought and installed from Market Place on PC. Plane worked great. Came back to have another go the next day and fuel pump switch wouldn't highlight blue and couldn't be turned on. I deleted the aircraft folder from LocalCache, reinstalled from Market Place, and it worked fine. Then came back the following the day and the switch was inoperable again.