In the Settings menu there is a number in the lower right corner. Mine is 4.2.1.8. I suspect this is the game version. Anyone that has Book 5 version of code installed, would you post your number?

I downloaded the latest code some time ago but not sure I ever installed it. So I'm looking for something in-game that will definitely tell me.

Sorry, no, the versions beginning with 4 only comprise Books 1 to 4. And as there have been some decided changes to Book 1 with the Book 5 update, you will have to download the entire game again to install in any case.

The latest is 5.3.1 and should show as such in your account.

Hope you'll have fun!

Thank you for the great response!