What doesn't work? It doesn't install or it doesn't work in line with your expectations? The README is very clear on what this addon does and does not do.

This review makes no sense - are you sure you're commenting on the right addon?

1) It deploys using exactly the same mechanism as every other Mozilla addon which means clicking on "Add to Firefox" and then clicking on another button to accept the permissions. If you're having an issue with deployment you should contact Mozilla support because this isn't the fault of this add-on.

2) How is two small bullet-pointed sentences "unnecessarily wordy"? There's also an image to show how the addon looks when you use the context menu. How isn't that helping?

3) Reduce what functions? What web-page?

4) I have no idea what this means: "A few weeks ago using Opera this process was almost "one button press" after media detail input(720/1080, audio setting."

Always to your browser default download folder, or the last folder you last saved something. There should be a record of the downloads in the browser. Just open/find location from there.

Can you explain what you're trying to download (the URL)?