Use .Net Windows Control in a VFP form

I try to use .net Visual Component developed with Visual Studio 2005 (C#) in a Visual FoxPro form.

I've just created a new "Windows Control Library" in VS2005. I've put a RichTextBox on it. And I've make it COM visible. I've register successfully this assembly with REGASM /CODEBASE.

I a VFP form, I've put a button with this code:

thisForm.AddObject('test','olecontrol','WindowsControlLibrary2.UserControl1')
thisForm.test.visible=.T.

But nothing appears on this form.

Thanks in advance for help.

Regards,

Guy