Well, I tried this, it's so cool!!

(bblean)
[HKEY_CLASSES_ROOT\Folder\shell]
@="bblean"
[HKEY_CLASSES_ROOT\Folder\shell\bblean]
[HKEY_CLASSES_ROOT\Folder\shell\bblean\command]
@="blackbox.exe -exec @bbcore.showmenu %L"
[HKEY_CLASSES_ROOT\Drive\shell]
@="bblean"
[HKEY_CLASSES_ROOT\Drive\shell\bblean]
[HKEY_CLASSES_ROOT\Drive\shell\bblean\command]
@="blackbox.exe -exec @bbcore.showmenu %L"
(blackbox.exe may need full path)
then...
(bb)run: c:\winnt -> It shows the folder in a bblean menu 
I'm sorry /\/\inimal, this probably has nothing to do with what you asked for...
It's cool anyway, if only bblean menu would let me browse up to [..] folder... that'd be wonderful hehe