Hi rsheinrich and welcome,
Hmmm, not sure. So you double-clicked on the email attachment (regkey) and restarted the app and it still shows as trial, eh?
If you click on the ? mark icon , upper right of the app and then click about on the dropdown, does it fails to show you as having a registered copy?
I'm guessing your answers are yes to both...maybe a problem with the regkey.
First off, click on this link and retrieve it.
You should receive it in a matter of seconds.
Be certain you are requesting the Fab5 key and not Fab3-4