EpiGroupBox / rectangle input control - child element background color

I am working on a configurator and I want to group controls together. When I place controls on to the group box they don’t take on the background color of the groupbox. How can I make the controls children of the rectangle / EpiGroupBox or share its background color?

I was trying to use the tutorial by @josecgomez (Jose C Gomez) but that only changed the background color of the list part of the combo and not the label part.

Well after digging around with ILSpy I figured out how to do it, in case anyone else ever wants to know:


Were Section1 is my group box and CmbManufacturer is the combo box I want to add to the group box.

Hmm, actually this seems to be screwing up the data binding or something, when ever I select a value for the combo box now I get the following error:

Error Detail

Message: Object reference not set to an instance of an object.
Program: Erp.Lib.Configurator.dll
Method: RefreshTextInControls

Client Stack Trace

at Erp.Lib.Configurator.Runtime.InputFieldPropertiesLib.RefreshTextInControls(InputCollection InputControls, String ColumnName, String value)
at Erp.UI.Cfg.TESTfd47df31e6c34e94901b081e02af8543.Controllers._Pianowire_ConfiguratorController._Pianowire_ConfiguratorPage1_ColumnChanged(Object sender, DataColumnChangeEventArgs e) in c:\Users\epurdy\AppData\Local\Temp\ConfigDump\Client_Pianowire_ConfiguratorController.cs:line 3213
at System.Data.DataColumnChangeEventHandler.Invoke(Object sender, DataColumnChangeEventArgs e)
at System.Data.DataTable.OnColumnChanged(DataColumnChangeEventArgs e)
at Erp.BO.Cfg.TESTfd47df31e6c34e94901b081e02af8543._Pianowire_ConfiguratorDataSet._Pianowire_ConfiguratorPage1DataTable.OnColumnChanged(DataColumnChangeEventArgs e) in c:\Users\epurdy\AppData\Local\Temp\ConfigDump\Client_Pianowire_ConfiguratorDataSet.cs:line 2359
at System.Data.DataRow.set_Item(DataColumn column, Object value)
at System.Data.DataRowView.SetColumnValue(DataColumn column, Object value)
at System.Data.DataRowView.set_Item(String property, Object value)
at Ice.Lib.Framework.EpiUltraCombo.updateDataSource(Object sender, Boolean forceUpdate)

Anyone have any idea why that might be?