The .net framework RichTextBox uses the 2.0 RichEdit control, I dont see your RichTextBoxEx class loading the msftedit.dll and specifying the following in the CreateParams to load the 5.0 control?
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Id #7153 | Release:
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| Updated: Aug 23 2010 at 1:21 PM by dmex | Created: Aug 23 2010 at 1:21 PM by dmex