To reproduce:
RadGroupBox1.GroupBoxElement.Header.Fill.Shape = New RoundRectShape(16, True, False, True, False)

Workaround:

RadGroupBox1.GroupBoxElement.Header.Fill.Shape = New OfficeShape()

Please refer to the attached screenshot. You will notice that the back color for the radio button differs from group box color. 

Workaround: this.radGroupBox1.BackColor =  Color.FromArgb (37, 37, 38);

The mnemonic key should activate the first control in the group box.

To reproduce:

 1. drag a radgroupbox into form
 2. drag 3 radpanels into radgroupbox
 3. set the 3 radpanels' dock = dockstyle.top
 4. set radgroupbox. autosize = true
 5. drag a radbutton into form and out of radgroupbox
 6. add click eventhandler to radbotton with below code

private void Button1_Click(object sender, EventArgs e)
{
       RadPanel2.Visible = !RadPanel2.Visible;
}

7. run app,  click the button continuously,  you will see that the width of the RadGroupBoxwill increase.

Workaround:

Set the AutoSize property to false and prior to hiding/showing the panel modify the size of the RadGroupBox

When you mouse hover the white border of the content area of RadGroupBox in HighContrastBlack and then you mouse leave it, the border disappears.

1. Create a new project and edit its resources file.
2. Open the string resources designer.
3. Change the Access Modifier to public in order to create public properties.
4. Add a new string resource with an empty value.
5. Add RadGroupBox on the form and open the Designer.cs file.
6. You will see that the HeaderImageKey and FooterImageKey properties point to the newly added resource which is wrong.

FIX. RadGRoupBox - header should be positioned accordingly in RightToLeft mode

1. Add a RadGroupBox control on a form
2. Change its theme to Office2007Black
3. Drop a textbox control inside the group box.
4. Set its Multiline property to true.
5. Set its Dock property to Fill.

If there is a control in RadGroupBox which exceeds the bounds of RadGroupBox and the AutoScroll property is true, you normally get scrollbars. However, after scrolling a bit, you will notice that there are redrawing issues with RadGroupBox.

FIX. RadGroupBox AutoSize property is not taken into consideration

When the GroupBoxStyle is Office, the default padding does not look ok when a control is docked to fill in RadGroupBox. The padding should either be (10, 30, 10, 10) or (0, 10, 0, 0).