Remove open close buttons

I have a FGR 222 that I use to control my Projector screen. I want to remove the Open close buttons and only keep the down / stop / up buttons.

I have tried to remove the open / close buttons from the WindowCovering json
More specificly this one

{ "ControlGroup": "1", "ControlType": "button", "top": "1.5", "left": "1", "Label": { "lang_tag": "ui7_cmd_open", "text": "Open" }, "Display": { "Service": "urn:upnp-org:serviceId:Dimming1", "Variable": "LoadLevelStatus", "Value": "100", "Top": 60, "Left": 50, "Width": 75, "Height": 20 }, "Command": { "Service": "urn:upnp-org:serviceId:Dimming1", "Action": "SetLoadLevelTarget", "Parameters": [ { "Name": "newLoadlevelTarget", "Value": "100" } ] }, "ControlCode": "wc_open" }

Changing the label text have no effect either. How can I remove the buttons?