Vista Tutorial - BUG: Images or Sound folder: Default operation changed from "open" to other

Hello,

I need a context menu entry in every folder and file, so I added one
into the registry path
HKEY_CLASSES_ROOT\AllFileSystemObjects\Shell\test with default
value=test and key Command=c:\text.exe %1 (both REG_SZ types).

Ths works for all normal files and folders, but if I create a new
folder on the desktop and copy only image files into it, vista
recognizes it as image folder, and suddenly my test operation becomes
the default operation for double click (bold in context menu), while
"open" is it not any more.

Is this a Vista bug? Are there any workarounds?

Thanks!

Problem solved. The default entry in the key "Shell" needs to be
"Open".

Jens