Game Server IP Config on PhotonControl shows nothing

Hi.
I would like to develop a multiplayer game working on LAN with PhotonServer.

While my laptop connects to an usual Wi-Fi network, it works well.
However While it connects to a LAN that I setup, something wrong happen on PhotonControl.
When I mouseover a menu "Game Server IP Config", no selection is showed up and a big blank white panel appears instead.

I have attempted to find solutions for this issue, but any thread or article like it has not been found yet.

I apologize for my poor English.
Any advise or comment will be appreciated.

Thank you.