Use new Multiple PSK feature for guest Wifi?!

Hello,

i want to have a simple guest wifi SSID using WPA2-PSK but with two different PSKs. One PSK changing every day and one which lasts a week or so. Is this possible by using the new Multi_PSK feature of WLM 8.5? And if, HOW? I tried to configure it myself but ran into deadlocks and the usermanual gives no clue how to do it, just telling the input fields.

Can somebody help?