Description

...

• We name the configuration key "CustomPickSteps". We name each step like Text or Date step. 
• You can use any naming.

    // Step 1

    [EventSubscriber(ObjectType::Codeunit, Codeunit::"MOB WMS Reference Data", 'OnGetReferenceData_OnAddRegistrationCollectorConfigurations', '', true, true)]
    local procedure OnGetReferenceData_OnAddRegistrationCollectorConfigurations(var _Steps: Record "MOB Steps Element")
    begin
        // Define a key for the step(s)
        _Steps.InitConfigurationKey('CustomPickSteps');

        // Create steps and set default values
        _Steps.Create_TextStep(35, 'TextStep', 'HeaderText');
        _Steps.Create_DateStep(45, 'DateStep', 'HeaderText');
        _Steps.Create_InformationStep(55, 'InfoStep', 'HeaderText', 'Label', 'HelpLabel');
    end;

Step 2

Include the step in "...OnAddStepsToAnyLine"-event

...

    // Step 2

    [EventSubscriber(ObjectType::Codeunit, Codeunit::"MOB WMS Pick", 'OnGetPickOrderLines_OnAddStepsToAnyLine', '', true, true)]
    local procedure MyOnGetPickOrderLines_OnAddStepsToAnyLine(_RecRef: RecordRef; var _BaseOrderLineElement: Record "MOB Ns BaseDataModel Element")
    var
        WarehouseActivityLine: Record "Warehouse Activity Line";
    begin
        _BaseOrderLineElement.Create_StepsByReferenceDataKey('CustomPickSteps');

        if (_RecRef.Number = Database::"Warehouse Activity Line") then begin
            _RecRef.SetTable(WarehouseActivityLine);

            // Overwrite Step values with information from pick line 
            _BaseOrderLineElement.SetValue('RegisterExtraInfo', STRSUBSTNO('CustomPickSteps{[InfoStep][helpLabel][Description is: "%1"][DateStep][defaultValue][%2][TextStep][defaultValue][%3]}',
                                            WarehouseActivityLine."Description",                               // Info step
                                            MobToolbox.Date2TextResponseFormat(20300101D),     // Date step
                                            WarehouseActivityLine."Description"));                            // Text step
        end;
    end;

• Set value "RegisterExtraInfo". 
• Using this syntax
  

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