Please run the attached sample project and refer to the attached screenshots. RadPropertyGrid doesn't respect the Description attribute.

 this.radPropertyGrid1.SelectedObject = new Item(123,"Item", ExposureMode.FullAuto);

public class Item
{
    public int Id { get; set; }

    public string Name { get; set; }

    public ExposureMode Mode { get; set; }

    public Item(int id, string name, ExposureMode mode)
    {
        this.Id = id;
        this.Name = name;
        this.Mode = mode;
    }
}

public enum ExposureMode
{
    [Description("Full Auto")]
    FullAuto,
    [Description("Auto Filter, Fixed Exposure")]
    AutoFilFixedExp,
    [Description("Fixed Filter, Auto Exposure")]
    FixedFilAutoExp,
    [Description("Fixed Filter, Fixed Exposure")]
    FullFixed
}

Office2010silver theme showing different result with  2017.2.613 version my font size became very small.

To reproduce:

        public RadForm1()
        {
            InitializeComponent();
             
            this.radPropertyGrid1.SelectedObject = new Item("zero", "uniqueId","alpha");

            this.radPropertyGrid1.EnableSorting = true;
            SortDescriptor sort = new SortDescriptor("Value", ListSortDirection.Ascending);
            this.radPropertyGrid1.SortDescriptors.Add(sort);
        }

        public class Item
        {
            public string Text { get; set; }
            
            public string Identifier { get; set; }

            public string Value { get; set; }

            public Item(string text, string identifier, string value)
            {
                this.Text = text;
                this.Identifier = identifier;
                this.Value = value;
            }
        }

Workaround#1: Set SortOrder to None

this.radPropertyGrid1.SortOrder = SortOrder.None;

Workaround#2: use a custom comparer:
            this.radPropertyGrid1.SortDescriptors.Add(sort);

            this.radPropertyGrid1.PropertyGridElement.PropertyTableElement.ListSource.CollectionView.Comparer = new MyComparer();

        public class MyComparer : IComparer<Telerik.WinControls.UI.PropertyGridItem>
        {
            int IComparer<Telerik.WinControls.UI.PropertyGridItem>.Compare(Telerik.WinControls.UI.PropertyGridItem x, Telerik.WinControls.UI.PropertyGridItem y)
            {
                if (x.Value != null && y.Value != null)
                {
                    return x.Value.ToString().CompareTo(y.Value.ToString());
                }
                return 0;
            }
        }

Problem: I'd like to filter the properties to be displayed by their category names defined by the Category attribute. Based on the doc here (https://docs.telerik.com/devtools/winforms/controls/propertygrid/features/filtering), my understanding is to add a FilterDescriptor like this: New FilterDescriptor ("Category", FilterOperator.Contains, "some category name"). But it turned out to only filter by property name, not category name. Any misunderstanding or possible issue? Thank you for looking into this.

Reproduce:

1. Define a class like this:

    Private Class TestClass
        <Category("Cat1")> Public Property Property1 As Integer = 1
        <Category("Cat1")> Public Property Property2 As String = "Test 2"
        <Category("Cat2")> Public Property Property3 As String = "Test 3"
    End Class

2. Initialize a RadPropertyGrid in the Form.Load event:

        Dim testObj As New TestClass
        RadPropertyGrid1.EnableFiltering = True
        Dim filter As New FilterDescriptor("Category", FilterOperator.Contains, "2")
        RadPropertyGrid1.FilterDescriptors.Add(filter)
        RadPropertyGrid1.SelectedObject = testObj

3. The right property to be displayed should be Property3, but it turned out to be Property2

Example project: attached.

Thank you team!

1. Create a custom property item

2. Enable grouping

3.Scroll up and down

4.NullReferenceException occurs