When in a server, in the customization/deploy screen: press ESC, you see the main menu. In order to get back to what I was doing I select Resume Game.

Observed: You see the spectator screen. There is no help on how to return to the customization/deploy screen. This is frustrating.
Expected: return to the customization/deploy screen instead.

Workaround: press M to return to the player customization/deploy screen.