Enter the address you used at checkout and we will send your key straight back to it.
We look up purchases made with that address and email the key back to it. Your key is sent only to the address that bought it, so there is nothing to click and no password to set. If nothing arrives within a few minutes, check your spam folder.
You may have bought with a different address, perhaps a work one or a PayPal account with its own email. Try those first. If you are still stuck, email md@twain.md with the approximate date of purchase and we will find it for you.
In Twain, open the app menu and choose Enter Licence, then paste the key. Licences are verified on your Mac, so they keep working with no internet connection, and one licence covers every Mac you own.