There's no need to know the installed version, since "installed version" is not a concept that doesn't make much sense, with a program that is constantly updated, with an automatic notification system that will tell you when an update is available.
So, to know if there's an update, in case you missed the last notification, select "Check Live Update" from the "Couatl Live Update" menu, and it will tell you if you need an update, and what the update does, so you can exit the sim, run the FSDT Live Update, and get the latest version.