Hi folks,this is my first post so please forgive if I get this wrong.
I too was looking for the exe under the Microsoft Store Install process but eventually found it under OS Drive letter \ Users \ 'yourname' \ Appdata \ Local \ Microsoft \ WindowsApps.
Inside that folder there is a list of various subfolders of which one is MicrosoftFlightSimulator_'then some letters and numbers' which containes the 'exe'
The 'exe' is also listed on it's own under the subfolders. I opened the properties of both and made them Run as Admin. Anyway hope this is of help to some of you.
Malcolm