I'm using the LE FLUFFE that was present in the converter of last year, the drag and drop works ..
It doesn't work if the Convert.exe loads Le fluffie, if you just open Le Fluffie your self there is no issue.
Well at least on my Win8.1 PC it doesn't.
Its also why I said if you have issues with it, download the tool again.
All that has changed is I stopped the Convert.exe loading Le Fluffie after the conversion is done & placed an Le Fluffie.exe in the root directory. (It's a shortcut to "Tools\Le Fluffie\Le Fluffie.exe")