Corrupt file type registrations cause issues with Edit/View

I am currently running the Windows 8 Dev Preview, but I don't believe this to be related to that, but rather to the developer preview of Visual Studio 11. The installer for VS11 has some bugs, so it writes some file type registrations with corrupted paths. So instead of the path to the application, it contains the string "$(reg.COMMONIDE)$(reg.EXE_NAME)". This, for example, is the case for the association information for .config files.
Now, I use the Edit feature in SmartFTP quite often to edit .NET config files on web sites. This suddenly did not work, even when I specifically assinged .config files to use Notepad++ as the editor in SmartFTP Options. After som troubleshooting, I discovered that SmartFTP was still reading the association information for .config files from the registry and tripping up on the malformed paths left by VS11. Correcting these paths made it work.
I don't believe that SmartFTP should let corrupt registry information disable the View/Edit feature like this. Rather, it should fall back to the default editor in Options - and in cases like mine, where an editor is explicitly specified, it shouldn't even read from the registry, since it does not need to look up the editor.