How do I prevent an empty registry key from being automatically deleted?

[EasyGoin12000]

I'm using Wix v3 to write a value to the Run registry key. During uninstall when my value is removed and leaves the Run key empty, the MSI engine removes the Run key. That may or may not be a big deal, but as a system registry key I would prefer if the Run key was left behind. Microsoft suggests that I create a dummy registry value with a "+" plus in the name field to prevent the key from being removed. Wix prevents this and generates this error - The RegistryValue/@name attribute's value, '+', is incorrect. It should not contain values of '+', '-', or '' when the RegistryValue/@value attribute is empty. Instead, use the proper element and attributes: for Name='+' use RegistryKey/@action='createKey', for Name='-' use RemoveRegistryKey/@action='removeOnUninstall', for Name='' use RegistryKey/@action='createAndRemoveOnUninstall'. Using those suggestions don't solve the problem. Any suggestions would be welcome.

Thanks.
Troy.