I've realised, that with some icons, they do not show up.
Like the IE7 icon...
getting :
ab3595ebae7c075420a8e35c84287767{0;BUNDLE.CouldNot ParseBitmap;System.ArgumentException:
Parameter is not valid. at System.Drawing.Bitmap..ctor(Stream stream) at
Novell.Zenworks.AppModule.AppActionItem.OverLayAnd GrayBytes(Byte[]
iconbytes)}

in the logs...