For me the preview doesn't work and the live automation works actually, here's a base where I've set it up and it works in case it's helpful

Interesting, so you've added 'Name' as field in your base to pull through? I interpreted 'User who took action' to mean the name on your user profile, because it also offers email address and ID?

Nope, it's from the "User who took action" step:

I am having the same issue and I looked at your example Adam but based on the preview it didn't work for you either. Can you explain a little more?

Hello, I managed to get this working in the end. You have to add a field to your base which is a 'User' field - see screenshot below. You can populate this as yourself or any users within your group, and then utilise that field in your automations. Let me know if that works! 

Yeap, the preview doesn't work and the live automation works:

Email:

If it's not working for you I'd be happy to take a look at it if you can provide a read-only invite link