Custom post type – Users not seen

I have a custom post type, called Press Mentions (pressmentions).
Stream is properly recognising the posts, but it is not displaying the users.
Instead, I’m seeing a “WP” logo and “N/A”.
See screengrab here: http://i.imgur.com/a6cnAhC.png

How can I fix this?
I note that Stream should work with Custom Post Types.
What should I be looking for?

Thanks.

https://ww.wp.xz.cn/plugins/stream/