DT Pro refuses to delete directories in the Image Catalog

[jeanluc.f]

Hi,
I am on Windows Vista.
I wanted to delete the directory made for a CD-ROM image (DT Pro failed to create it) and it was impossible from the DT Pro interface.
I finally found that there was directories called:
C:\Users\{MyName}\AppData\Roaming\DAEMON Tools Pro\ImageCatalog\Root\{NameOfTheCD}\{ListOfNumbers }\
who contained one icon file...
I suppose that DT Pro did not want to delete the directory because it was not empty. But, why wasn't it empty?
I deleted the file and the directory with the Windows CMD Shell and it disappeared from DT Pro, as I wanted.
Is it a bug, or is it possible to delete this icon file from DT Pro?
Thanks.