We don't control how other websites do their business or technologies they use. If they decide to make changes to their website, it will break the Downloader experience. Every time they have done this, we have managed to make our Downloader compatible. This being said, if in the future, they make changes to their websites, it will break Downloader as well.
Lastly, we are not responsible for contact numbers of YouTube. If they don't have one, you have to take it up with them and not RealNetworks. We are 2 different companies.