I'll note this as a bug as this should at least support the club type forums.
This will be a bit more complex but will note for a future feature version.
What is your feed source? If it only contains 20 or so videos, then that's the limit on how far back the Videos app can import unfortunately.
Not currently and I'm not sure if I could realistically make it as seamless as you might expect. If there was a "playlist" of videos for example, you would probably need to click "next" manually rather then have it triggered at the end of the video playback.