Yeah, I believe the problem is the digital copy. Well, what media player you used to play the Spider-Man 2 on your computer?
Is it available for the iPad?
If not, I suppose you may need to do converting the digital copy with converters again.
Hmm, you want to download the videos on iOS? how about do the work on Mac?
found this video downloader on Mac app store, which stated can download Vimeo videos: https://itunes.apple.com/us/app/ifunia-videodownloader/id413622895?mt=12