ActiveX control not working in Excel 2010

I have a simple text box that is made visible while my VBA programming is running ("Sheet1.TextBox1.Visible=True") and made not visible at the end. It works fine in Excel 2003 (XP). But in Excel 2010 (Windows 7 and IE8) the text box appears just for a fraction of a second when the code makes it not visible.
I've tried registering the text box through Developer tab/Controls/Insert/Register custom/msdxm.ocx (whatever that is - it was the only .ocx file that accepted the registration).
I've also tried turning off all possible ActiveX blockers in Excel 2010, Windows 7 (including turning off UAC) and my Norton security but nothing allows the control to work as it does with Excel 2003 and XP.
Can anyone help?

After a lot of fiddling, I managed to get the control to appear but the method does not make sense. I explain what I did in case someone might be able to explain why it works. After the statement to make the control visible, I added a time delay using (with Hr and Min current time and Sec 5 seconds more):
waitTime = TimeSerial(Hr, Min, Sec)
Application.Wait waitTime
Any thoughts on why this works and perhaps therefore what is stopping the visible statement working by itself?