Yes, Total Access Statistics is completely backward compatible. Every version of Total Access Statistics runs scenarios created in earlier versions. Just convert your database to the new version of Access, and Total Access Statistics (for that version of Access) can run them.
The scenario settings live in your database. Specifically, they are stored within the system table called "usysTStatScenarios" (you may need to turn on the MS Access option to view hidden/system table objects before this table object displays within your navigation pane in).
If you'd like to move your Total Access Statistics scenario settings into a new database, simply import the following Total Access Statistics this system table into your new database.