Im running it on win11 and win 10 on the same machine with 2 different boot drives. On win11 the msfs dir is on the G drive, on win 10 its on the F drive, its the same base install. When I upgraded su7 on win11 it asked me where the dir was, I pointed it to the dir and then did the install. Now when I booted into win10 I had to download the steam end of things again, but when it got to the update screen and wanted to know where msfs was installed I had to tell the F drive (which is the G drive in win11). So anyways, after I pointed it to that drive, it didnt download anything else and ran just fine.
Now I can run under win 11 or win 10 without having the game installed twice…