That's odd I've not had anyone else have that issue. I'll post a version 0.8 Beta in a minute.. It'll just have the changes provided by @shadow256 and a little bit of a code tidy. I'll also post an AIO version which should have all of the files posted by @mpham and @Meliodas2255 and my Gui in the correct places, you'll just need to provide your prod.keys file
Version 0.8beta files should be uploaded now.. However I had a thought, its possible the conversion isn't working because you don't have full permission to the folder your running from, Right click the menu.exe and run as administrator might solve this issue for you.
same result,i always end with a working forwarder and a ? icon,tried different formats,programs and even mspaint suggested by the gui and always end in convertion error