When adding Surrogate Key lookups, a new window is popped open from the dim table in the staging area.
If, for some reason, that table didn't have System Control Fields displayed, there is not a way to enable them in the New Window... so I have to go back and find that dimension table in the full project tree and choose Show System Control Fields.
Overall, the right click menus should not be different between the full project tree and the New Window Popup. It would save quite a lot of time if more, or all of the menu options were also available in the popup window.
This would be a big timesaver in a large project.
Project Tree right click:
New Window Popup Right Click: