Larian Studios Forums Divinity: Original Sin 2 Divinity - Original Sin 2 - General D:OS 2 Kickstarter through Paypal

You should be able to create an account on the Larian Vault site now. That was described in the last D:OS 2 Kickstarter update in regards to claiming a copy of the D:OS Enhanced Edition, for those with it as a tier reward or add-on.

Basically, log in or create an account on the Vault, then click on 'D:OS2 Kickstarter', fill in your Paypal email address and click on the Link button.
If the tier you backed included a copy of the EE, you can choose a Steam or GOG key in the 'Your choices & input' section.