You don’t need to install it - it runs in a browser tab. However, because you don’t have a registration code you won’t be able to use it immediately. Register for a code at Kee Vault - Secure, simple, Open Source password management - launched 28th May 2019 | Product Hunt and we’ll most likely get it emailed out to you within a couple of days, a week at the most.
The upcoming version 3.1 of the browser extension adds a button under that message to help you get signed-in because we know there’s currently a lack of guidance about what to do if you first reach that message in the way that you have.
Fair point. I think from the Kee Vault perspective this is a temporary problem that should be much easier once there’s no need for us to limit the number of users by using the registration code system.
For KeePass, well, that’s part of the reason I created Kee Vault - it’s not all that easy. It certainly can be done though if you can’t wait for a Kee Vault access code or can’t afford the £2/month Kee Vault subscription. Take a look at Installing Kee with KeePassRPC for KeePass Password Safe (instructions)