One functionality issue, two cosmetic issues, and a request:
I just now downloaded this add-on for the sake of downloading all the ".ogg" audio files from a particular web page, but the add-on did not recognize them as audio files -- it displayed them in the "External links" tab instead of the "Video & Audio" tab. I had to go to the External links tab, then use Filter > URL includes this text: ogg to be able to gather them all so that I could select them all.
Except for that, the add-on did what it was supposed to do.
Cosmetically, when hovering the cursor over the add-on button, the tool-tip text says "Video Downloader Professional" instead of "All Downloader Professional". Was that the add-on's old name? Secondly, under General settings > Select language, "English" is spelled the German way: "Englisch", which I find little strange. All the rest of the text on the settings page is spelled in standard English.
Finally, I would like the option to select where to download files to.