The printer settings are greyed out by default because they require administrative privileges to alter them. You can still view the settings, just not modify them.
To make changes, you have to go to the General tab, and press the Advanced Settings (or something) with the UAC icon on it. It will ask you to confirm you want to relaunch the app with administrative privileges.
From this moment on, you can make changes in all tabs, including ports but also Device settings.
Do note, that although for this dialog, you do need admin settings, the printer preferences are usually also accessible and do not require administrative privileges.