Promote the main Point of an Equipment Switch not working

Dear all,

I changed to use “Promote the main Point of an Equipment” for main UI and like it as my equipment grew. Using a switch with widgetOrder=0 worked but brought up unexpected behavior.
For example I have two items, one for on/off, one for brightness control and would like to use the switch status as main point to be shown. The code below makes the switch appearing but no control works.

Group            gShellyTerrasseZaunbeleuchtung                         "Terrasse Zaunbeleuchtung"                                        <light>          (gTerrasse)                                   ["Lightbulb"]              {ga="Light"}
Switch           ShellyTerrasseZaunbeleuchtungRelaySwitch               "Schalter"                                                        <light>          (gShellyTerrasseZaunbeleuchtung)              ["Switch","Light"]         {ga="lightPower", channel="mqtt:topic:Shelly_Terrasse_Zaunbeleuchtung:Power", autoupdate="false", stateDescription=""[options="ON=An, OFF=Aus"],widgetOrder="0"}
Number           ShellyTerrasseZaunbeleuchtungRelayBrightness           "Helligkeit [%d %%]"                                                               (gShellyTerrasseZaunbeleuchtung)              ["Control"]                {ga="lightBrightness", channel="mqtt:topic:Shelly_Terrasse_Zaunbeleuchtung:Helligkeit", autoupdate="false", listWidget="oh-slider-item"[min=0,max=100,step=1,scale=true,releaseOnly=true,scaleSteps=10,label=true]}

Is it a bug or some wrong usage / configuration?

any idea or hint?