Using Scrivener on two laptops

Hi, can anyone help? We bought and installed Scrivener on one of our Mac laptops two months ago. We wanted to install it on the other but when we tried to do that via the AppStore (where we bought the original version), it only installed the trial version. Suspect we need the serial number (? although the instructions don’t say so) but can’t find that - went via the Literature And Latte page to retrieve it a few weeks ago but never received it.
The trial version runs out in two weeks and my husband is scared he’ll lose all his work - any help gratefully received!

It could be there was an old version of the demo on the other computer from before? It’s impossible for the App Store to send you a demo version (Apple wouldn’t allow anything remotely like that in their store, we even strip out the code for all of that rather than just disable the features visually, they wouldn’t allow that either). But what can happen if you already have the demo installed is that the button in the MAS where you’d click to download is replaced with a button to that merely launches the program.

At any rate, the problem should be easy to solve. With the software closed, go into your Applications folder and move the copy of Scrivener to the Trash, then restart the App Store program if necessary. You should now see an “Install” button beside Scrivener in the “Purchases” tab.

Thanks so much, Amber - and he won’t lose any of his work in the trial version when we do this?