The Remote Desktop Services properties dialog displays a subset of the Remote Desktop Services configuration on a server. Only the Remote control tab is editable; Security, Client settings, and Session timeouts are read-only. For settings the dialog doesn't expose, use the Group Policy editor or the RDS deployment console.

Right-click the server on the Servers tab and choose Administration > Remote Desktop Services properties....
The dialog has four pages selected from a list on the left.
Picks the policy the server applies to incoming shadow requests. Five radio buttons:
A Controlled by policy label appears in the top-right of the tab when Group Policy is enforcing the setting; in that case the radio buttons are greyed out.
Changes are applied via WMI when you click OK.

Read-only. Three values:

Read-only. Five toggle switches show the current client feature redirection state, plus one color depth value:
The toggles reflect the server's current settings but can't be changed here. A Controlled by policy label appears when Group Policy locks the tab.

Read-only limits, in minutes. Each value shows No limit when nothing is enforced.
The bottom toolbar has Refresh to re-read values from the server, plus OK and Cancel.